Targeting euchromatic histone lysine methyltransferases sensitizes colorectal cancer to histone deacetylase inhibitors.

Epigenetic dysregulation is an important feature of colorectal cancer (CRC). Combining epigenetic drugs with other antineoplastic agents is a promising treatment strategy for advanced cancers. Here, we exploited the concept of synthetic lethality to identify epigenetic targets that act synergistically with histone deacetylase (HDAC) inhibitors to reduce the growth of CRC. We applied a pooled CRISPR-Cas9 screen using a custom sgRNA library directed against 614 epigenetic regulators and discovered that knockout of the euchromatic histone-lysine N-methyltransferases 1 and 2 (EHMT1/2) strongly enhanced the antiproliferative effect of clinically used HDAC inhibitors. Using tissue microarrays from 1066 CRC samples with different tumor stages, we showed that low EHMT2 protein expression is predominantly found in advanced CRC and associated with poor clinical outcome. Cotargeting of HDAC and EHMT1/2 with specific small molecule inhibitors synergistically reduced proliferation of CRC cell lines. Mechanistically, we used a high-throughput Western blot assay to demonstrate that both inhibitors elicited distinct cellular mechanisms to reduce tumor growth, including cell cycle arrest and modulation of autophagy. On the epigenetic level, the compounds increased H3K9 acetylation and reduced H3K9 dimethylation. Finally, we used a panel of patient-derived CRC organoids to show that HDAC and EHMT1/2 inhibition synergistically reduced tumor viability in advanced models of CRC.

Evaluating the Distribution, Quality, and Educational Value of Videos Related to Knee Instability Exercises on the Social Media Platform TikTok.

Introduction TikTok, a globally popular short-form video platform, offers a unique space for healthcare professionals to share advice, particularly under common conditions such as knee pain or instability. Despite its popularity, doubts persist regarding the reliability of medical information disseminated on TikTok. This study aimed to evaluate the quality of TikTok videos as a source of patient information on knee instability, recognizing the need for a comprehensive assessment of potential misinformation on this influential social media platform. Methods A search for "knee stability exercises" on TikTok yielded 448 videos, of which 187 met the inclusion criteria. These videos were categorized by source and evaluated using the Knee Exercise Education Scoring Tool (KEEST) and an information analysis questionnaire, DISCERN. Results General user videos (69.84%) had notably lower DISCERN scores than healthcare professional videos (29.1%) across all categories (P < 0.001, P = 0.282, P = 0.131, and P = 0.010). The DISCERN scores were inversely linked to video metrics (views, likes, comments, favorites, and shares). General user videos were largely of poor quality (66.4%), whereas healthcare professional videos spanned poor (61.8%), fair (28.2%), good (9.1%), and excellent (1.8%) categories. Both general users (12.31/25) and healthcare professionals (12.18/25) exhibited average quality according to KEEST standards (P = 0.809), with an intriguing inverse correlation between video popularity and DISCERN score. Conclusion Healthcare professionals demonstrated superior evidence-based content (DISCERN), whereas both groups were comparatively educated on treatment plans and effects (KEEST). TikTok's prevalent knee instability videos lack quality, proper sourcing, treatment risk information, and explanation. Moreover, popularity is inversely correlated with quality, and healthcare professionals appear to offer better evidence-based content. TikTok's role in healthcare highlights the importance of ensuring accurate information and implementing content quality regulations.

Sphingosine-sphingosine-1-phosphate pathway regulates trophoblast differentiation and syncytialization.

Sphingosine and sphingosine-1-phosphate (S1P) are involved in regulating cell differentiation. This study postulated that changes in sphingolipid biosynthesis and metabolism are important in trophoblast syncytialization and therefore examined the production, metabolism and actions of sphingosine and S1P during spontaneous trophoblast differentiation and fusion in vitro. Significant declines in intracellular sphingosine concentration (P≤0.05) and sphingosine kinase 1 (SPHK1) expression (P≤0.01) were observed during trophoblast syncytialization. Secreted S1P concentrations dropped steeply after 72h, before rising to basal concentrations with syncytialization. Intracellular S1P concentrations were undetectable throughout. Treating cells with exogenous sphingosine (P≤0.01), S1P (P≤0.001) or a specific SPHK1 inhibitor (P≤0.05) for up to 72h in culture significantly inhibited trophoblast differentiation (measured as reduced human chorionic gonadotrophin production); effects on other biochemical and morphological markers of differentiation were absent or inconsistent. Phosphorylation of Akt, an established down-stream target of S1P that spontaneously declines with trophoblast differentiation, was markedly reduced by S1P (P≤0.05). In conclusion, changes in the sphingosine-S1P pathway are involved in the regulation of trophoblast differentiation in term human placenta. Dysregulation of sphingolipid homeostasis could, therefore, disrupt placental formation and function with deleterious consequences for pregnancy outcome.

Effect of vitamin E supplementation on carbogen-induced amelioration of noise induced hearing loss in man.

The study explores the effect of occupational noise on oxidative stress status and prophylactic effect of Vitamin E and carbogen (5% CO 2 +95%O 2 ) breathing in alleviating the oxidative damage and conserving the hearing in human volunteers exposed to intense occupational noise. Plasma total antioxidant status, blood glutathione (GSH), malondialdehyde (MDA), antioxidant enzyme activities of GSH peroxidase (EC 1.11.1.9, GPx), superoxide dismutase (EC 1.15.1.1; SOD) in erythrocytes, nitric oxide and nitric oxide synthase in plasma were assessed before and after 6 days of administration of Vitamin E and Carbogen. Results of the study indicate that the exposure to noise for 6 days increased blood concentration of MDA, decreased concentrations of reduced GSH, antioxidant enzyme activity of SOD and plasma total antioxidant status in control (noise) group. Vitamin E- supplemented group showed decline in oxidative stress reflected by significant decrease in blood concentration of MDA and increase in antioxidant enzyme activity of erythrocyte SOD. Results of audiometric studies revealed that breathing of carbogen prevented the development of temporary threshold shift; thereby reducing the risk of noise induced hearing loss.

Chalcone Scaffolds as Anticancer Drugs: A Review on Molecular Insight in Action of Mechanisms and Anticancer Properties.

Cancer is the deadliest disease worldwide and the development of safer chemical entities to treat cancer is one of the major challenges of medicinal chemistry. The emergence of new cases every year and the development of multiple drug resistance against available molecular entities have turned the focus of researchers towards natural products. Chalcones are pharmacologically active compounds, present in plants, which have been derivatized and screened by many researchers for the treatment of cancer. Chalcones, consist of 1,3-diaryl-2- propen-1-one, is one such class exhibiting broad anticancer activities against various cancerous cell lines. The objective of this review article is to analyze the antitumor activity of the reported chalcones via distinct mechanisms adopted by these molecules underlying their inhibitory activity. The primary focus of this review is to bring the attention of researchers towards the latest and important chalcones and their derivatives having potent anticancer activity adding their possible action of mechanisms against cancerous cell lines The recent literature was surveyed and it was found that chalcone analogs with electron donating groups, indolyl, quinolone, pyrazol-ol, hydroxyaminobenzamide, hydroxamic acid and pyridyl- indole groups have shown promise as potential anticancer agents following various mechanisms. Most chalcones were found to induce significant cell cycle arrest at G2/M phase hence leading to apoptosis. A number of synthetic chalcones exhibited higher efficacy due to their ability of potent tubulin polymerization as well as dynamic enzyme inhibitory activity. This review is an immense compilation of research regarding the mechanism of action of chalcones and their identification as a promising anticancer agent for future drug developments. Thus, this review article would pave the way and provide ample opportunities to design future generations of novel, highly efficacious anticancer molecules with minimal toxicity.

Regulation of trophoblast migration and survival by a novel neural regeneration peptide.

Although placental trophoblast migration is tightly controlled in an autocrine/paracrine manner, the nature of chemoattractive factors facilitating and directing this biological activity remains largely elusive. Neural regeneration peptides (NRP), a recently discovered peptide family, stimulate neuronal migration, differentiation and survival of post-natal neurons within the murine central nervous system. Based on the neural-repair related activities of these peptides and parallels between neuronal and placental cell behaviour patterns, this study postulated that they play a role in placental development, in particular trophoblast migration and survival and investigated the role of a newly discovered NRP motif (NNZ-4920), which exhibits about 70% homology to the mouse NRP motif sequence and is homologous to a 13-mer fragment within the N-terminus of human CAPS2, in trophoblast migration and survival regulation. NNZ-4920 significantly enhanced trophoblast migration by 51% (P<0.01) compared with controls and protected against stress induced by serum withdrawal and tumour necrosis factor-alpha/interferon-gamma treatment, at femtomolar concentrations, with efficacy similar to epidermal growth factor. CAPS2 expression was detected in purified term trophoblast and decidual cells. In conclusion, the placenta may be a source of NRP-related gene expression. Its encoded peptide products exert biological effects on term trophoblast migration and survival in vitro.

Mycobacterium fortuitum-induced ER-Mitochondrial calcium dynamics promotes calpain/caspase-12/caspase-9 mediated apoptosis in fish macrophages.

Mycobacterium fortuitum is a natural fish pathogen. It induces apoptosis in headkidney macrophages (HKM) of catfish, Clarias sp though the mechanism remains largely unknown. We observed M. fortuitum triggers calcium (Ca2+) insult in the sub-cellular compartments which elicits pro-apototic ER-stress factor CHOP. Alleviating ER-stress inhibited CHOP and attenuated HKM apoptosis implicating ER-stress in the pathogenesis of M. fortuitum. ER-stress promoted calpain activation and silencing the protease inhibited caspase-12 activation. The study documents the primal role of calpain/caspase-12 axis on caspase-9 activation in M. fortuitum-pathogenesis. Mobilization of Ca2+ from ER to mitochondria led to increased mitochondrial Ca2+ (Ca2+)m load,, mitochondrial permeability transition (MPT) pore opening, altered mitochondrial membrane potential (ΔΨm) and cytochrome c release eventually activating the caspase-9/-3 cascade. Ultra-structural studies revealed close apposition of ER and mitochondria and pre-treatment with (Ca2+)m-uniporter (MUP) blocker ruthenium red, reduced Ca2+ overload suggesting (Ca2+)m fluxes are MUP-driven and the ER-mitochondria tethering orchestrates the process. This is the first report implicating role of sub-cellular Ca2+ in the pathogenesis of M. fortuitum. We summarize, the dynamics of Ca2+ in sub-cellular compartments incites ER-stress and mitochondrial dysfunction, leading to activation of pro-apoptotic calpain/caspase-12/caspase-9 axis in M. fortuitum-infected HKM.

Calcium and Superoxide-Mediated Pathways Converge to Induce Nitric Oxide-Dependent Apoptosis in Mycobacterium fortuitum-Infected Fish Macrophages.

Mycobacterium fortuitum causes 'mycobacteriosis' in wide range of hosts although the mechanisms remain largely unknown. Here we demonstrate the role of calcium (Ca+2)-signalling cascade on M. fortuitum-induced apoptosis in headkidney macrophages (HKM) of Clarias sp. M. fortuitum could trigger intracellular-Ca+2 influx leading to the activation of calmodulin (CaM), protein kinase C alpha (PKCα) and Calmodulin kinase II gamma (CaMKIIg). Gene silencing and inhibitor studies established the role of CaM in M. fortuitum pathogenesis. We noted that CaMKIIg activation is regulated by CaM as well as PKCα-dependent superoxide anions. This is altogether first report of oxidised CaMKIIg in mycobacterial infections. Our studies with targeted-siRNA and pharmacological inhibitors implicate CaMKIIg to be pro-apoptotic and critical for the activation of extra-cellular signal regulated kinase 1/2 (ERK1/2). Inhibiting the ERK1/2 pathway attenuated nitric oxide synthase 2 (NOS2)-induced nitric oxide (NO) production. Conversely, inhibiting the NOS2-NO axis by specific-siRNA and inhibitors down-regulated ERK1/2 activation suggesting the crosstalk between ERK1/2 and NO is essential for pathogenesis induced by the bacterium. Silencing the NOS2-NO axis enhanced intracellular bacterial survival and attenuated caspase-8 mediated activation of caspase-3 in the infected HKM. Our findings unveil hitherto unknown mechanism of M. fortuitum pathogenesis. We propose that M. fortuitum triggers intracellular Ca+2 elevations resulting in CaM activation and PKCα-mediated superoxide generation. The cascade converges in common pathway mediated by CaMKIIg resulting in the activation of ERK1/2-NOS2 axis. The crosstalk between ERK1/2 and NO shifts the balance in favour of caspase dependent apoptosis of M. fortuitum-infected HKM.

Infection of Bacterial Endosymbionts in Insects: A Comparative Study of Two Techniques viz PCR and FISH for Detection and Localization of Symbionts in Whitefly, Bemisia tabaci.

Bacterial endosymbionts have been associated with arthropods and large number of the insect species show interaction with such bacteria. Different approaches have been used to understand such symbiont- host interactions. The whitefly, Bemisia tabaci, a highly invasive agricultural pest, harbors as many as seven different bacterial endosymbionts. These bacterial endosymbionts are known to provide various nutritional, physiological, environmental and evolutionary benefits to its insect host. In this study, we have tried to compare two techniques, Polymerase chain reaction (PCR) and Flourescence in situ Hybridisation (FISH) commonly used for identification and localization of bacterial endosymbionts in B. tabaci as it harbors one of the highest numbers of endosymbionts which have helped it in becoming a successful global invasive agricultural pest. The amplified PCR products were observed as bands on agarose gel by electrophoresis while the FISH samples were mounted on slides and observed under confocal microscope. Analysis of results obtained by these two techniques revealed the advantages of FISH over PCR. On a short note, performing FISH, using LNA probes proved to be more sensitive and informative for identification as well as localization of bacterial endosymbionts in B. tabaci than relying on PCR. This study would help in designing more efficient experiments based on much reliable detection procedure and studying the role of endosymbionts in insects.

Ameliorating ER-stress attenuates Aeromonas hydrophila-induced mitochondrial dysfunctioning and caspase mediated HKM apoptosis in Clarias batrachus.

Endoplasmic reticulum (ER)-stress and unfolding protein response (UPR) has not been implied in Aeromonas hydrophila-pathogenicity. We report increased expression of the ER-stress markers: CHOP, BiP and phospho-eIF2α in A. hydrophila-infected headkidney macrophages (HKM) in Clarias batrachus. Pre-treatment with ER-stress inhibitor, 4-PBA alleviated ER-stress and HKM apoptosis suggesting ER-UPR critical for the process. The ER-Ca(2+) released via inositol-triphosphate and ryanodine receptors induced calpain-2 mediated superoxide ion generation and consequent NF-κB activation. Inhibiting NF-κB activation attenuated NO production suggesting the pro-apoptotic role of NF-κB on HKM pathology. Calpain-2 activated caspase-12 to intensify the apoptotic cascade through mitochondrial-membrane potential (ψm) dissipation and caspase-9 activation. Altered mitochondrial ultra-structure consequent to ER-Ca(2+) uptake via uniporters reduced ψm and released cytochrome C. Nitric oxide induced the cGMP/PKG-dependent activation of caspase-8 and truncated-Bid formation. Both the caspases converge onto caspase-3 to execute HKM apoptosis. These findings offer a possible molecular explanation for A. hydrophila pathogenicity.

Molecular characterization and analysis of bacterial diversity in Aleurocanthus woglumi (Hemiptera: Aleyrodidae).

Aleurocanthus woglumi Ashby (Hemiptera: Aleyrodidae), commonly referred to as citrus blackfly, is a sap-sucking hemipteran insect. Although polyphagous, citrus is its most preferred host plant. Samples of this insect were collected from Murraya koenigii (L.). The cytochrome c oxidase subunit I gene (mtCO1)-based analysis by sequencing helped in molecular identification of the insect. Phylogenetic analysis of cytB-nd1-LrDNA showed the coevolution of A. woglumi with its primary bacterial symbiont Portiera. Sequencing a 16S rDNA library from insect DNA revealed three bacterial phylotypes, namely, Portiera, Wolbachia, and Erwinia chrysanthemi. Further, we used fluorescence in situ hybridization to visualize the endosymbionts in a whole mount of A. woglumi. Culturable bacteria were obtained on different media and were classified on the basis of 16S rDNA. In total, 30 bacterial phylotypes belonging to 14 different genera, namely, Bacillus, Kocuria, Micrococcus, Staphylococcus, Paenibacillus, Rhodococcus, Rummellibacillus, Arthrobacter, Curtobacterium, Psychrobacillus, Listeria, Brevibacillus, Bhargavae, and Pantoea, were isolated by culturable methods.

Zotarolimus- versus everolimus-eluting stents for unprotected left main coronary artery disease.

OBJECTIVES: This study sought to compare the safety and efficacy of the zotarolimus-eluting stent (ZES) and the everolimus-eluting stent (EES) for treatment of unprotected left main coronary artery (uLMCA) disease. BACKGROUND: The second-generation ZES and EES have reduced the risk of restenosis in large patient cohorts. However, their comparative performance in uLMCA lesions is not known. METHODS: In this study, patients with symptomatic coronary artery disease undergoing percutaneous coronary intervention for uLMCA lesions were randomly assigned to receive either a ZES (n = 324) or an EES (n = 326). The primary endpoint was the combined incidence of death, myocardial infarction, and target lesion revascularization at 1 year. Secondary endpoints were definite or probable stent thrombosis at 1 year and angiographic restenosis based on analysis of the left main coronary artery area at follow-up angiography. RESULTS: At 1 year, the cumulative incidence of the primary endpoint was 17.5% in the ZES group and 14.3% in the EES group (relative risk: 1.26; 95% confidence interval [CI]: 0.85 to 1.85; p = 0.25). Three patients in the ZES group (0.9%) and 2 patients in the EES group (0.6%) experienced definite or probable stent thrombosis (p > 0.99). All-cause mortality at 1 year was equal in the 2 groups (5.6%; relative risk: 1.00; 95% CI: 0.52 to 1.93; p = 0.98). Angiographic restenosis occurred in 21.5% of patients in the ZES group and 16.8% in the EES group (relative risk: 1.28; 95% CI: 0.86 to 1.92; p = 0.24). CONCLUSIONS: Within the statistical limitations of the present study, treatment of uLMCA lesions with a ZES or an EES provided comparable clinical and angiographic outcomes at 1-year follow-up.

Ceramide biosynthesis and metabolism in trophoblast syncytialization.

Sphingolipid mediators such as ceramide are pleiotropic regulators of cellular growth, differentiation and apoptosis. We investigated the role of ceramide biosynthesis, metabolism and actions in term human cytotrophoblasts syncytialized over 7 days in culture. Intracellular C16 ceramide levels increased modestly after 3 days in culture, then declined. Ceramidase was present at particularly high levels in syncytialized trophoblasts; inhibition of ceramidase reduced the degree of cell fusion. Exposure to short chain C8 ceramide or aSMase enhanced secretion of the differentiation marker hCG without affecting fusion or cell viability. In contrast, pharmacological inhibition of ceramidase reduced the extent of fusion. Inhibition of the ceramide-responsive JNK and PP2A pathways did not abolish the effects of ceramide, and JNK phosphorylation was unresponsive to ceramide; however, ceramide significantly inhibited phosphorylation of Akt. This study suggests that changes in ceramide biosynthesis and metabolism play a differential role in the biochemical and morphological features of trophoblast differentiation.

Transport of lipids by ABC proteins: interactions and implications for cellular toxicity, viability and function.

Members of the ATP-binding cassette (ABC) family of membrane-bound transporters are involved in multiple aspects of transport and redistribution of various lipids and their conjugates. Most ABC transporters localize to the plasma membrane; some are associated with liquid-ordered cholesterol-/sphingolipid-rich microdomains, and to a lesser extent the membranes of the Golgi and endoplasmic reticulum. Hence, ABC transporters are well placed to regulate plasma membrane lipid composition and the efflux and redistribution of structural phospholipids and sphingolipids during periods of cellular stress and recovery. ABC transporters can also modulate cellular sensitivity to extrinsic pro-apoptotic signals through regulation of sphingomyelin-ceramide biosynthesis and metabolism. The functionality of ABC transporters is, in turn, modulated by the lipid content of the microdomains in which they reside. Cholesterol, a major membrane microdomain component, is not only a substrate of several ABC transporters, but also regulates ABC activity through its effects on microdomain structure. Several important bioactive lipid mediators and toxic lipid metabolites are also effluxed by ABC transporters. In this review, the complex interactions between ABC transporters and their lipid/sterol substrates will be discussed and analyzed in the context of their relevance to cellular function, toxicity and apoptosis.