Deinococcus radiodurans-derived membrane vesicles protect HaCaT cells against H2O2-induced oxidative stress via modulation of MAPK and Nrf2/ARE pathways.

BACKGROUND: Deinococcus radiodurans is a robust bacterium that can withstand harsh environments that cause oxidative stress to macromolecules due to its cellular structure and physiological functions. Cells release extracellular vesicles for intercellular communication and the transfer of biological information; their payload reflects the status of the source cells. Yet, the biological role and mechanism of Deinococcus radiodurans-derived extracellular vesicles remain unclear. AIM: This study investigated the protective effects of membrane vesicles derived from D. radiodurans (R1-MVs) against H2O2-induced oxidative stress in HaCaT cells. RESULTS: R1-MVs were identified as 322 nm spherical molecules. Pretreatment with R1-MVs inhibited H2O2-mediated apoptosis in HaCaT cells by suppressing the loss of mitochondrial membrane potential and reactive oxygen species (ROS) production. R1-MVs increased the superoxide dismutase (SOD) and catalase (CAT) activities, restored glutathione (GSH) homeostasis, and reduced malondialdehyde (MDA) production in H2O2-exposed HaCaT cells. Moreover, the protective effect of R1-MVs against H2O2-induced oxidative stress in HaCaT cells was dependent on the downregulation of mitogen-activated protein kinase (MAPK) phosphorylation and the upregulation of the nuclear factor E2-related factor 2 (Nrf2)/antioxidant response element (ARE) pathway. Furthermore, the weaker protective capabilities of R1-MVs derived from ΔDR2577 mutant than that of the wild-type R1-MVs confirmed our inferences and indicated that SlpA protein plays a crucial role in R1-MVs against H2O2-induced oxidative stress. CONCLUSION: Taken together, R1-MVs exert significant protective effects against H2O2-induced oxidative stress in keratinocytes and have the potential to be applied in radiation-induced oxidative stress models.

Immunostimulatory Potential of Extracellular Vesicles Isolated from an Edible Plant, Petasites japonicus, via the Induction of Murine Dendritic Cell Maturation.

Extracellular vesicles (EVs) have recently been isolated from different plants. Plant-derived EVs have been proposed as potent therapeutics and drug-delivery nanoplatforms for delivering biomolecules, including proteins, RNAs, DNAs, and lipids. Herein, Petasites japonicus-derived EVs (PJ-EVs) were isolated through a series of centrifugation steps and characterized using dynamic light scattering and transmission electron microscopy. Immunomodulatory effects of PJ-EVs were assessed using dendritic cells (DCs). PJ-EVs exhibited a spherical morphology with an average size of 122.6 nm. They induced the maturation of DCs via an increase in the expression of surface molecules (CD80, CD86, MHC-I, and MHC-II), production of Th1-polarizing cytokines (TNF-α and IL-12p70), and antigen-presenting ability; however, they reduced the antigen-uptake ability. Furthermore, maturation of DCs induced by PJ-EVs was dependent on the activation and phosphorylation of MAPK and NF-κB signal pathways. Notably, PJ-EV-treated DCs strongly induced the proliferation and differentiation of naïve T cells toward Th1-type T cells and cytotoxic CD8+ T cells along with robust secretion of IFN-γ and IL-2. In conclusion, our study indicates that PJ-EVs can be potent immunostimulatory candidates with an ability of strongly inducing the maturation of DCs.

Protective Effect of Polysaccharides Extracted from Cudrania tricuspidata Fruit against Cisplatin-Induced Cytotoxicity in Macrophages and a Mouse Model.

Although cisplatin is one of most effective chemotherapeutic drugs that is widely used to treat various types of cancer, it can cause undesirable damage in immune cells and normal tissue because of its strong cytotoxicity and non-selectivity. This study was conducted to investigate the cytoprotective effects of Cudrania tricuspidata fruit-derived polysaccharides (CTPS) against cisplatin-induced cytotoxicity in macrophages, lung cancer cell lines, and a mouse model, and to explore the possibility of application of CTPS as a supplement for anticancer therapy. Both cisplatin alone and cisplatin with CTPS induced a significant cytotoxicity in A549 and H460 lung cancer cells, whereas cytotoxicity was suppressed by CTPS in cisplatin-treated RAW264.7 cells. CTPS significantly attenuated the apoptotic and necrotic population, as well as cell penetration in cisplatin-treated RAW264.7 cells, which ultimately inhibited the upregulation of Bcl-2-associated X protein (Bax), cytosolic cytochrome c, poly (adenosine diphosphateribose) polymerase (PARP) cleavage, and caspases-3, -8, and -9, and the downregulation of B cell lymphoma-2 (Bcl-2). The CTPS-induced cytoprotective action was mediated with a reduction in reactive oxygen species production and mitochondrial transmembrane potential loss in cisplatin-treated RAW264.7 cells. In agreement with the results obtained above, CTPS induced the attenuation of cell damage in cisplatin-treated bone marrow-derived macrophages (primary cells). In in vivo studies, CTPS significantly inhibited metastatic colonies and bodyweight loss as well as immunotoxicity in splenic T cells compared to the cisplatin-treated group in lung metastasis-induced mice. Furthermore, CTPS decreased the level of CRE and BUN in serum. In summation, these results suggest that CTPS-induced cytoprotective action may play a role in alleviating the side effects induced by chemotherapeutic drugs.

Bombyx batryticatus Protein-Rich Extract Induces Maturation of Dendritic Cells and Th1 Polarization: A Potential Immunological Adjuvant for Cancer Vaccine.

Bombyx batryticatus, a protein-rich edible insect, is widely used as a traditional medicine in China. Several pharmacological studies have reported the anticancer activity of B. batryticatus extracts; however, the capacity of B. batryticatus extracts as immune potentiators for increasing the efficacy of cancer immunotherapy is still unverified. In the present study, we investigated the immunomodulatory role of B. batryticatus protein-rich extract (BBPE) in bone marrow-derived dendritic cells (BMDCs) and DC vaccine-immunized mice. BBPE-treated BMDCs displayed characteristics of mature immune status, including high expression of surface molecules (CD80, CD86, major histocompatibility complex (MHC)-I, and MHC-II), increased production of proinflammatory cytokines (tumor necrosis factor-α and interleukin-12p70), enhanced antigen-presenting ability, and reduced endocytosis. BBPE-treated BMDCs promoted naive CD4+ and CD8+ T-cell proliferation and activation. Furthermore, BBPE/ovalbumin (OVA)-pulsed DC-immunized mice showed a stronger OVA-specific multifunctional T-cell response in CD4+ and CD8+ T cells and a stronger Th1 antibody response than mice receiving differently treated DCs, which showed the enhanced protective effect against tumor growth in E.G7 tumor-bearing mice. Our data demonstrate that BBPE can be a novel immune potentiator for a DC-based vaccine in anticancer therapy.

Chrysin Derivative CM1 and Exhibited Anti-Inflammatory Action by Upregulating Toll-Interacting Protein Expression in Lipopolysaccharide-Stimulated RAW264.7 Macrophage Cells.

Although our previous study revealed that gamma-irradiated chrysin enhanced anti-inflammatory activity compared to intact chrysin, it remains unclear whether the chrysin derivative, CM1, produced by gamma irradiation, negatively regulates toll-like receptor (TLR) signaling. In this study, we investigated the molecular basis for the downregulation of TLR4 signal transduction by CM1 in macrophages. We initially determined the appropriate concentration of CM1 and found no cellular toxicity below 2 µg/mL. Upon stimulation with lipopolysaccharide (LPS), CM1 modulated LPS-stimulated inflammatory action by suppressing the release of proinflammatory mediators (cytokines TNF-α and IL-6) and nitric oxide (NO) and downregulated the mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) signaling pathways. Furthermore, CM1 markedly elevated the expression of the TLR negative regulator toll-interacting protein (Tollip) in dose- and time-dependent manners. LPS-induced expression of cell surface molecules (CD80, CD86, and MHC class I/II), proinflammatory cytokines (TNF-α and IL-6), COX-2, and iNOS-mediated NO were inhibited by CM1; these effects were prevented by the knockdown of Tollip expression. Additionally, CM1 did not affect the downregulation of LPS-induced expression of MAPKs and NF-κB signaling in Tollip-downregulated cells. These findings provide insight into effective therapeutic intervention of inflammatory disease by increasing the understanding of the negative regulation of TLR signaling induced by CM1.

Neuroprotective effect of Annona muricata-derived polysaccharides in neuronal HT22 cell damage induced by hydrogen peroxide.

Crude extracts and phytochemical compounds derived from Annona muricata leaves have been demonstrated to exert neuroprotective effects. However, the neuroprotective effects of Annona muricata leaves-derived polysaccharide extracts (ALPs) have not been investigated. ALP treatment was shown to induce concentration-dependent antioxidant activity in HT22 cells, and to increase cell viability in H2O2-treated HT22 cells. These effects were correlated with a decrease in major components of oxidation, including: Ca2+, ROS, and malondialdehyde (MDA). Mediators of the intracellular response to oxidation, including Bax, cytochrome c, and cleaved caspases-3, -8, -9, MAPKs, and NF-κB, were positively influenced by ALP treatment under conditions of H2O2-mediated oxidative stress. In addition, ALP restored the expression of superoxide dismutase (SOD) and associated signaling pathways (PARP, PI3K/AKT and Nrf2-mediated HO-1/NQO-1) following H2O2 treatment. These results provide new pharmacological evidence that ALP facilitates neuroprotection via prevention of neuronal oxidative stress and promotion of cell survival signaling pathways.Abbreviations: ABTS: 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonicacid); AD: Alzheimer's disease; ALP: polysaccharide extracts isolated from Annona muricata leaves; ARE: antioxidant response element; DPPH: 1,1-diphenyl-picrylhydrazyl; DCFH-DA: 2',7'-dichlorofluorescin diacetate; ECL: electrochemiluminescence; ERK: extracellular regulated kinase; FBS: Fetal bovine serum; FITC: fluorescein isothiocyanate; FRAP: ferric reducing antioxidant power; HO-1: Heme oxygenase-1; JNK: c-jun N-terminal kinase; MAPKs: mitogen-activated protein kinases; MDA: malondialdehyde; MMP: mitochondrial membrane potential; MTT: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide; NQO1: NAD(P)H:quinine oxidoreductase 1, Nrf2: nuclear factor-E2-related factor 2; PD: parkinson's disease; PI3K: phosphatidylinositol-3kinase; PVDF: polyvinylidene difluoride; ROS: reactive oxygen species; SOD: Superoxidedismutase; TPTZ: tripydyltriazine.

4-Hydroxybenzaldehyde Restricts the Intracellular Growth of Toxoplasma gondii by Inducing SIRT1-Mediated Autophagy in Macrophages.

Toxoplasma gondii is an intracellular protozoan parasite that infects approximately one third of the human popu- lation worldwide. Considering the toxicity and side effects of anti-toxoplasma medications, it is important to develop effec- tive drug alternatives with fewer and less severe off-target effects. In this study, we found that 4-hydroxybenzaldehyde (4- HBA) induced autophagy and the expression of NAD-dependent protein deacetylase sirtuin-1 (SIRT1) in primary murine bone marrow-derived macrophages (BMDMs). Interestingly, treatment of BMDMs with 4-HBA significantly reduced the number of macrophages infected with T. gondii and the proliferation of T. gondii in infected cells. This effect was impaired by pretreating the macrophages with 3-methyladenine or wortmannin (selective autophagy inhibitors) or with sirtinol or EX527 (SIRT1 inhibitors). Moreover, we found that pharmacological inhibition of SIRT1 prevented 4-HBA-mediated expres- sion of LC3-phosphatidylethanolamine conjugate (LC3-II) and the colocalization of T. gondii parasitophorous vacuoles with autophagosomes in BMDMs. These data suggest that 4-HBA promotes antiparasitic host responses by activating SIRT1- mediated autophagy, and 4-HBA might be a promising therapeutic alternative for the treatment of toxoplasmosis.

Therapeutic Potential of Gamma-Irradiated Resveratrol in Ulcerative Colitis via the Anti-Inflammatory Activity and Differentiation of Tolerogenic Dendritic Cells.

BACKGROUND/AIMS: New therapeutic strategies and the development of treatments against inflammatory bowel disease (IBD) require the initiation of immune tolerance and inhibition of excessive inflammation. Resveratrol, a polyphenolic compound, is a powerful immunosuppressor, but it can lead to apoptotic death of normal cells at high concentrations. When we induced a structural modification of resveratrol by gamma irradiation, we were able to investigate the potential tolerogenic and anti-inflammatory effect of a new radiolysis product (named γ-Res) during dendritic cell (DC) activation/differentiation. METHODS: The potential tolerogenic and anti-inflammatory effect of γ-Res were investigated by cytokine secretion, surface molecule expression, antigen uptake ability, antigen presenting ability, signaling pathway, and mixed lymphocyte reaction (MLR) assay using enzyme-linked immunosorbent assay (ELISA), western blot and flow cytometry. RESULTS: LPS-activated DCs treated with γ-Res exhibited alterations in their mature and functional statuses including a strongly inhibited cytokine production, surface molecule expression, antigen-presenting ability, and activated DC-induced T cell proliferation/activation. In addition, the DCs generated by the γ-Res treatment during DC differentiation induced a decreased surface molecule expression and increased IL-10 production without altering the levels of TNF-α and IL-12p70, thereby promoting the inhibition of T cell proliferation/activation and the induction of regulatory T cells via interaction with DCs in vitro. Furthermore, in the in vivo DSS-induced colitis model, γ-Res treatment conferred protective immunity with a decrease in IFN-γ+CD4+ and IL-17A+CD4+ T cells and imparted protection by reducing the disease activity and histological disease score and increasing the survival rate in dextran sulfate sodium (DSS)-induced colitis in mice. CONCLUSION: Thus, our results suggest that γ-Res may be an excellent candidate for use in IBD treatment.

GLM, a novel luteolin derivative, attenuates inflammatory responses in dendritic cells: Therapeutic potential against ulcerative colitis.

GLM, a luteolin derivative, shows anti-melanogenic effect via regulation of various signal molecules; however, it is unclear whether it also exerts anti-inflammatory effect. This study investigated the mechanisms of the anti-inflammatory effect of GLM on activated dendritic cells (DCs) to elucidate its therapeutic potential for ulcerative colitis. The anti-inflammatory effect of GLM was firstly investigated based on its effect on DCs maturation and T cells proliferation/activation. GLM treatment downregulated pro-inflammatory cytokine productions, surface molecule expression, and antigen-presenting ability for MHC-II complex in LPS-activated DCs. Importantly, anti-inflammatory effect induced by GLM treatment were independent of MAPK/NF-κB signaling pathways. Furthermore, DCs that were co-treated with LPS and GLM impaired the proliferation and activation of naïve CD4+ T cells. Interestingly, GLM exerted in vivo protective effect in DSS-induced colitis models by decreasing Th1, Th2, and Th17 cells and myeloperoxidase (MPO) levels, as well as restoring body weight, disease activity, and DSS-induced pathology. Based on these results, GLM was shown to be a potential candidate treatment for ulcerative colitis.

Neuroprotective effect of Capsicum annuum var. abbreviatum against hydrogen peroxide-induced oxidative stress in HT22 hippocampus cells.

Phenolic compounds isolated from pepper (Capsicum annum) have been demonstrated to have neuroprotective effects, whereas the physiological properties of Capsicum annuum var. abbreviatum (CAA) have not been studied. Thus, we investigate the chemical composition and neuroprotective activity of CAA extract (CAAE) in HT22 hippocampus cells against H2O2-induced neurotoxicity. CAAE treatment resulted in a significant protection of H2O2-exposed HT22, this protection ultimately occurred through an inhibition of MDA and ROS levels and an induction of SOD activity. Furthermore, CAAE treatment reduced H202-induced apoptosis though decreasing the expression of pro-apoptotic factors (Bax, cytochrome c, and cleaved caspases-3) while increasing the expression of the anti-apoptotic factors (Bcl-2), as well as the accumulation of nucleus-Nrf2-mediated HO-1 signaling. Interestingly, CAAE has a high concentration of unique phenolic compositions (chlrogenic acid, tangeretin, etc.) than other capsicum annum extracts. Altogether, these findings suggest that CAAE can be a useful natural resource for alleviating neurodegenerative diseases.

Trusting Social Media as a Source of Health Information: Online Surveys Comparing the United States, Korea, and Hong Kong.

BACKGROUND: The Internet has increasingly become a popular source of health information by connecting individuals with health content, experts, and support. More and more, individuals turn to social media and Internet sites to share health information and experiences. Although online health information seeking occurs worldwide, limited empirical studies exist examining cross-cultural differences in perceptions about user-generated, experience-based information compared to expertise-based information sources. OBJECTIVE: To investigate if cultural variations exist in patterns of online health information seeking, specifically in perceptions of online health information sources. It was hypothesized that Koreans and Hongkongers, compared to Americans, would be more likely to trust and use experience-based knowledge shared in social Internet sites, such as social media and online support groups. Conversely, Americans, compared to Koreans and Hongkongers, would value expertise-based knowledge prepared and approved by doctors or professional health providers more. METHODS: Survey questionnaires were developed in English first and then translated into Korean and Chinese. The back-translation method ensured the standardization of questions. Surveys were administered using a standardized recruitment strategy and data collection methods. RESULTS: A total of 826 participants living in metropolitan areas from the United States (n=301), Korea (n=179), and Hong Kong (n=337) participated in the study. We found significant cultural differences in information processing preferences for online health information. A planned contrast test revealed that Koreans and Hongkongers showed more trust in experience-based health information sources (blogs: t451.50=11.21, P<.001; online support group: t455.71=9.30, P<.001; social networking sites [SNS]: t466.75=11.36, P<.001) and also reported using blogs (t515.31=6.67, P<.001) and SNS (t529.22=4.51, P<.001) more frequently than Americans. Americans showed a stronger preference for using expertise-based information sources (eg, WebMD and CDC) compared to Koreans and Hongkongers (t360.02=3.01, P=.003). Trust in expertise-based information sources was universal, demonstrating no cultural differences (Brown-Forsythe F2,654=1.82, P=.16). Culture also contributed significantly to differences in searching information on behalf of family members (t480.38=5.99, P<.001) as well as to the goals of information searching. CONCLUSIONS: This research found significant cultural differences in information processing preferences for online health information. Further discussion is included regarding effective communication strategies in providing quality health information.

Exploring cultural differences in women's body weight perception: The impact of self-construal on perceived overweight and engagement in health activities.

We examined the cultural influence on perceived body weight and the level of health practices at a national and individual level. At a national level, we found that Japanese women (n = 80) overestimate body weight more than Korean (n = 82) and American (n = 63) women. At an individual level, individuals with interdependent self-construal were more prone to overestimate weight than those with independent self-construal (N = 182; American women). Based on the data, we identify that the relationship is mediated by self-criticism, and, importantly, it is self-criticism rather than perceived overweight that predicts the level of health activities. Health practitioners and campaign designers across cultures are recommended to concentrate on promoting positive body esteem instead of encouraging engagement in corrective health behaviors for weight loss.

Deep breathing in your hands: designing and assessing a DTx mobile app.

Digital Therapeutics (DTx) are experiencing rapid advancements within mobile and mental healthcare sectors, with their ubiquity and enhanced accessibility setting them apart as uniquely effective solutions. In this evolving context, our research focuses on deep breathing, a vital technique in mental health management, aiming to optimize its application in DTx mobile platforms. Based on well-founded theories, we introduced a gamified and affordance-driven design, facilitating intuitive breath control. To enhance user engagement, we deployed the Mel Frequency Cepstral Coefficient (MFCC)-driven personalized machine learning method for accurate biofeedback visualization. To assess our design, we enlisted 70 participants, segregating them into a control and an intervention group. We evaluated Heart Rate Variability (HRV) metrics and collated user experience feedback. A key finding of our research is the stabilization of the Standard Deviation of the NN Interval (SDNN) within Heart Rate Variability (HRV), which is critical for stress reduction and overall health improvement. Our intervention group observed a pronounced stabilization in SDNN, indicating significant stress alleviation compared to the control group. This finding underscores the practical impact of our DTx solution in managing stress and promoting mental health. Furthermore, in the assessment of our intervention cohort, we observed a significant increase in perceived enjoyment, with a notable 22% higher score and 10.69% increase in positive attitudes toward the application compared to the control group. These metrics underscore our DTx solution's effectiveness in improving user engagement and fostering a positive disposition toward digital therapeutic efficacy. Although current technology poses challenges in seamlessly incorporating machine learning into mobile platforms, our model demonstrated superior effectiveness and user experience compared to existing solutions. We believe this result demonstrates the potential of our user-centric machine learning techniques, such as gamified and affordance-based approaches with MFCC, which could contribute significantly to the field of mobile mental healthcare.

Immunostimulatory potential of extruded plant-based meat: effect of extrusion moisture level on macrophage activation.

In this study, the effect of different moisture levels in extruded plant-based meat on macrophage immunostimulation, and the potential of this meat as a protein source and a solution to environmental and economic challenges associated with conventional meat was investigated. To determine the effects of the extruded plant-based meat, cell viability assay, enzyme-linked immunosorbent assay, flow cytometry, and western blotting were performed. Low-moisture (LMME) and high-moisture meat extracts (HMME) showed higher potential to activate macrophages and regulate cytokine production than raw material extract. Treatment with LMME and HMME resulted in increased expression of CD80, CD86, and MHC class I/II proteins, indicating their potential to activate macrophages. Western blotting suggested that the immune activation observed in a previous study of macrophages was because of the phosphorylation of MAPKs and NF-κB. These findings suggest that extruded plant-based meat can potentially be used as an immunostimulatory food ingredient.

CM1, a Chrysin Derivative, Protects from Endotoxin-Induced Lethal Shock by Regulating the Excessive Activation of Inflammatory Responses.

Sepsis, a leading cause of death worldwide, is a harmful inflammatory condition that is primarily caused by an endotoxin released by Gram-negative bacteria. Effective targeted therapeutic strategies for sepsis are lacking. In this study, using an in vitro and in vivo mouse model, we demonstrated that CM1, a derivative of the natural polyphenol chrysin, exerts an anti-inflammatory effect by inducing the expression of the ubiquitin-editing protein TNFAIP3 and the NAD-dependent deacetylase sirtuin 1 (SIRT1). Interestingly, CM1 attenuated the Toll-like receptor 4 (TLR4)-induced production of inflammatory cytokines by inhibiting the extracellular-signal-regulated kinase (ERK)/MAPK and nuclear factor kappa B (NF-κB) signalling pathways. In addition, CM1 induced the expression of TNFAIP3 and SIRT1 on TLR4-stimulated primary macrophages; however, the anti-inflammatory effect of CM1 was abolished by the siRNA-mediated silencing of TNFAPI3 or by the genetic or pharmacologic inhibition of SIRT1. Importantly, intravenous administration of CM1 resulted in decreased susceptibility to endotoxin-induced sepsis, thereby attenuating the production of pro-inflammatory cytokines and neutrophil infiltration into the lung compared to control mice. Collectively, these findings demonstrate that CM1 has therapeutic potential for diverse inflammatory diseases, including sepsis.

Information needs, seeking behaviors, and support among low-income expectant women.

Previous studies have consistently found associations between low income and infant health outcomes. Moreover, although health information-seeking is a maternal behavior related to improved health outcomes, little is known about the health information-seeking behaviors and information needs of low-income pregnant women. The purpose of the current investigation was to examine the information needs, information-seeking behaviors, and perceived informational support of low-income pregnant women. Accordingly, the study recruited 63 expectant women enrolled in a subsidized prenatal care program in Milwaukee, Wisconsin, during two time periods: March-May 2011 and October-December 2011. Results indicated that participants relied heavily upon interpersonal sources of information, especially family and the father of the baby; rarely used the Internet for health-related information; and desired information beyond infant and maternal health, such as finding jobs and accessing community/government resources. Participants who used family members as primary sources of information also had significantly increased levels of perceived informational support and reduced uncertainty about pregnancy. Our findings have implications for the dissemination of pregnancy-related health information among low-income expectant women.

Agarolytic Pathway in the Newly Isolated Aquimarina sp. Bacterial Strain ERC-38 and Characterization of a Putative ß-agarase.

Marine microbes, particularly Bacteroidetes, are a rich source of enzymes that can degrade diverse marine polysaccharides. Aquimarina sp. ERC-38, which belongs to the Bacteroidetes phylum, was isolated from seawater in South Korea. It showed agar-degrading activity and required an additional carbon source for growth on marine broth 2216. Here, the genome of the strain was sequenced to understand its agar degradation mechanism, and 3615 protein-coding sequences were predicted, which were assigned putative functions according to their annotated functional feature categories. In silico genome analysis revealed that the ERC-38 strain has several carrageenan-degrading enzymes but could not degrade carrageenan because it lacked genes encoding κ-carrageenanase and S1_19A type sulfatase. Moreover, the strain possesses multiple genes predicted to encode enzymes involved in agarose degradation, which are located in a polysaccharide utilization locus. Among the enzymes, Aq1840, which is closest to ZgAgaC within the glycoside hydrolase 16 family, was characterized using a recombinant enzyme expressed in Escherichia coli BL21 (DE3) cells. An enzyme assay revealed that recombinant Aq1840 mainly converts agarose to NA4. Moreover, recombinant Aq1840 could weakly hydrolyze A5 into A3 and NA2. These results showed that Aq1840 is involved in at least the initial agar degradation step prior to the metabolic pathway that uses agarose as a carbon source for growth of the strain. Thus, this enzyme can be applied to development and manufacturing industry for prebiotic and antioxidant food additive. Furthermore, our genome sequence analysis revealed that the strain is a potential resource for research on marine polysaccharide degradation mechanisms and carbon cycling.

What message features influence the intention to share misinformation about COVID-19 on social media? The role of efficacy and novelty.

Given the amount of misinformation being circulated on social media during the COVID-19 pandemic and its potential threat to public health, it is imperative to investigate ways to hinder its transmission. To this end, this study aimed to identify message features that may contribute to misinformation sharing on social media. Based on the theory of social sharing of emotion and the extant research on message credibility, this study examined if emotions and message credibility serve as mechanisms through which novelty and efficacy of misinformation influence sharing intention. An online experiment concerning COVID-19 misinformation was conducted by employing a 2 (novelty conditions: high vs. low) × 2 (efficacy conditions: high vs. low) between-subjects design using a national quota sample in South Korea (N = 1,012). The findings suggested that, contrary to the expectation, the overall effects of novelty on sharing intention were negative. The specific mechanisms played significant and unique roles in different directions: novelty increased sharing intention by evoking surprise, while also exerting a negative influence on sharing intention through an increase in negative emotions and a decrease in positive emotions and message credibility. Consistent with the expectation, efficacy exhibited positive total effects on sharing intention, which was explained by higher levels of (self- and response-) efficacy of protective action increasing positive emotions and message credibility but decreasing negative emotions. The implications and limitations of the study are discussed.

Protective Effects of Bombyx batryticatus Protein-Rich Extract Against Cisplatin-Induced Nephrotoxicity in HEK293 Cells and a Mouse Model.

Cisplatin, a potent and prominent chemotherapeutic drug, has considerable side effects, including nephrotoxicity, which limits its therapeutic application and efficacy. Therefore, the development of agents that protect normal cells while preserving cisplatin's chemotherapeutic properties is of utmost importance. This study aimed to explore the protective effects of Bombyx batryticatus protein-rich extract (BBPE) against cisplatin-induced nephrotoxicity in a cisplatin-treated mouse model and human embryonic kidney (HEK293) cells. Apoptosis was assessed in HEK293 cells to determine the cytoprotective effects of BBPE and its effects on the generation of cisplatin-induced reactive oxygen species (ROS) and mitochondrial transmembrane potential (MTP) collapse. Although cisplatin induced nephrotoxicity in HEK293 cells, pretreatment with BBPE showed significant protective effects against cisplatin-induced nephrotoxicity by regulating the expression levels of pro- and antiapoptotic proteins. The cytoprotective effects of BBPE were mediated by decreased ROS production and MTP loss in cisplatin-treated HEK293 cells. The in vitro results were confirmed in the cisplatin-treated mouse model. Pretreatment with BBPE protected against cisplatin-induced nephrotoxicity by restoring malondialdehyde, superoxide dismutase, and catalase levels in kidney tissue and blood urea nitrogen and creatinine serum levels. Furthermore, histopathological assessment and terminal dUTP nick end-labeling staining showed that BBPE mitigated cisplatin-induced nephrotoxicity in kidney tissues. Overall, BBPE may act as a potent agent for alleviating cisplatin-induced nephrotoxicity, thereby increasing the safety of cisplatin-based chemotherapy.

Polysaccharides from Annona muricata leaves protect against cisplatin­induced cytotoxicity in macrophages by alleviating mitochondrial dysfunction.

Cisplatin is a prominent chemotherapeutic agent that can induce significant damage to normal cells. Therefore, it is important to develop agents that protect normal cells without influencing the chemotherapeutic effect of cisplatin. The present study was conducted to explore the protective effects of Annona muricata leaf polysaccharides (ALPS) against cisplatin­induced toxicity in macrophages. Apoptosis was assessed in macrophages and lung cancer cells to investigate the cytoprotective effect of ALPS, their effect on the production of cisplatin­induced reactive oxygen species (ROS) and the loss of the mitochondrial transmembrane potential (MTP). Cisplatin, when used alone or in combination with ALPS, showed significant toxicity against A549 and H460 lung cancer cells. However, cisplatin­induced cytotoxicity was suppressed by cotreatment of RAW 264.7 macrophages with ALPS. ALPS significantly inhibited the upregulation of Bax, cytosolic cytochrome c and caspases­3, ­8 and ­9. Moreover, ALPS resulted in the cleavage of PARP and downregulation of Bcl­2 levels in a concentration­dependent manner, which ultimately led to a reduction in the apoptotic and necrotic populations of cisplatin­treated RAW 264.7 macrophages. The suppression of the apoptotic signaling pathways was mediated through the reduction of ROS and MTP loss in cisplatin­treated RAW 264.7 macrophages. In addition, ALPS alleviated cell damage by suppressing the mitochondrial apoptotic pathways in cisplatin­treated bone marrow­derived macrophages. Together, these findings suggested that ALPS may alleviate the toxic side effects of chemotherapeutic agents and act as a potential candidate for use as an effective adjuvant therapy.