Recent advances in regulating lipid metabolism to prevent coronary heart disease.

The pathogenesis of coronary heart disease is a highly complex process, with lipid metabolism disorders being closely linked to its development. Therefore, this paper analyzes the various factors that influence lipid metabolism, including obesity, genes, intestinal microflora, and ferroptosis, through a comprehensive review of basic and clinical studies. Additionally, this paper delves deeply into the pathways and patterns of coronary heart disease. Based on these findings, it proposes various intervention pathways and therapeutic methods, such as the regulation of lipoprotein enzymes, lipid metabolites, and lipoprotein regulatory factors, as well as the modulation of intestinal microflora and the inhibition of ferroptosis. Ultimately, this paper aims to offer new ideas for the prevention and treatment of coronary heart disease.

Synergism of TNF-α and IFN-ß triggers human airway epithelial cells death by apoptosis and pyroptosis.

Cytokine release syndrome, also called cytokine storm, could cause lung tissue damage, acute respiratory distress syndrome (ARDS) and even death during SARS-CoV-2 infection. However, the underlying mechanisms of cytokine storm still remain unknown. Among these cytokines, the function of TNF-α and type I IFNs especially deserved further investigation. Here, we first found that TNF-α and IFN-ß synergistically induced human airway epithelial cells BEAS-2B death. Mechanistically, the combination of TNF-α and IFN-ß led to the activation of caspase-8 and caspase-3, which initiated BEAS-2B apoptosis. The activated caspase-8 and caspase-3 could further induce the cleavage and activation of gasdermin D (GSDMD) and gasdermin E (GSDME), which finally resulted in pro-inflammatory pyroptosis. The knock-down of caspase-8 and caspase-3 could effectively block the activation of GSDMD and GSDME, and then the death of BEAS-2B induced by TNF-α and IFN-ß. In addition, pan-caspase inhibitor Z-VAD-FMK (ZVAD) and necrosulfonamide (NSA) could inhibit BEAS-2B death induced by TNF-α and IFN-ß. Overall, our work revealed one possible mechanism that cytokine storm causes airway epithelial cells (AECs) damage and ARDS. These results indicated that blocking TNF-α and IFN-ß-mediated AECs death may be a potential target to treat related viral infectious diseases, such as COVID-19.

RIPK1 dephosphorylation and kinase activation by PPP1R3G/PP1γ promote apoptosis and necroptosis.

Receptor-interacting protein kinase 1 (RIPK1) is a key regulator of inflammation and cell death. Many sites on RIPK1, including serine 25, are phosphorylated to inhibit its kinase activity and cell death. How these inhibitory phosphorylation sites are dephosphorylated is poorly understood. Using a sensitized CRISPR whole-genome knockout screen, we discover that protein phosphatase 1 regulatory subunit 3G (PPP1R3G) is required for RIPK1-dependent apoptosis and type I necroptosis. Mechanistically, PPP1R3G recruits its catalytic subunit protein phosphatase 1 gamma (PP1γ) to complex I to remove inhibitory phosphorylations of RIPK1. A PPP1R3G mutant which does not bind PP1γ fails to rescue RIPK1 activation and cell death. Furthermore, chemical prevention of RIPK1 inhibitory phosphorylations or mutation of serine 25 of RIPK1 to alanine largely restores cell death in PPP1R3G-knockout cells. Finally, Ppp1r3g-/- mice are protected from tumor necrosis factor-induced systemic inflammatory response syndrome, confirming the important role of PPP1R3G in regulating apoptosis and necroptosis in vivo.

The Different Effects of IFN-ß and IFN-γ on the Tumor-Suppressive Activity of Human Amniotic Fluid-Derived Mesenchymal Stem Cells.

Current studies have shown that type I or II interferon-modified mesenchymal stem cells have great potential for the application of tumor-targeted therapy, but the underlying mechanism remains largely elusive. Here, we compared the different effects of IFN-ß and IFN-γ on the antitumor activity of human amniotic fluid-derived mesenchymal stem cells (AFMSCs) and revealed the potential mechanism. In detail, AFMSCs primed with IFN-ß or IFN-ß plus IFN-γ, not IFN-γ, inhibited the proliferation of cancer cells in an immunocompetent mouse H460 subcutaneous model, although they all inhibited the proliferation of cancer cells in an immunocompromised mouse H460 subcutaneous model. TRAIL expressed by IFN-ß- or IFN-γ-primed AFMSCs specifically exerted the antitumor effect of AFMSCs. AFMSCs primed with IFN-γ highly expressed immunosuppressive molecule IDO1, but IFN-ß counteracted the IFN-γ-initiated IDO1 expression. 1-MT (IDO1 inhibitor) decreased TRAIL, but increased IDO1 expression in AFMSCs primed with interferon. As a result, AFMSCs primed with IFN-ß or IFN-γ had the antitumor activity, and 1-MT failed to enhance the antitumor effect of IFN-γ-primed AFMSC in vitro and in the immunocompromised mouse H460 subcutaneous model. Furthermore, the expression of TRAIL in AFMSCs was upregulated by apoptotic cancer cells and this positive feedback intensified the antitumor effects of IFNs-primed AFMSCs. The different target gene expression profiles of AFMSCs regulated by IFN-ß and IFN-γ determined the different antitumor effects of IFN-ß- and IFN-γ-primed AFMSCs on tumor cells. Our finding may help to explore a clinical strategy for cancer intervention by understanding the antitumor mechanisms of MSCs and interferon.

Screening and Identification of ssDNA Aptamer for Human GP73.

As one tumor marker of HCC, Golgi Protein 73 (GP73) is given more promise in the early diagnosis of HCC, and aptamers have been developed to compete with antibodies as biorecognition probes in different detection system. In this study, we utilized GP73 to screen specific ssDNA aptamers by SELEX technique. First, GP73 proteins were expressed and purified by prokaryotic expression system and Nickle ion affinity chromatography, respectively. At the same time, the immunogenicity of purified GP73 was confirmed by Western blotting. The enriched ssDNA library with high binding capacity for GP73 was obtained after ten rounds of SELEX. Then, thirty ssDNA aptamers were sequenced, in which two ssDNA aptamers with identical DNA sequence were confirmed, based on the alignment results, and designated as A10-2. Furthermore, the specific antibody could block the binding of A10-2 to GP73, and the specific binding of A10-2 to GP73 was also supported by the observation that several tumor cell lines exhibited variable expression level of GP73. Significantly, the identified aptamer A10-2 could distinguish normal and cancerous liver tissues. So, our results indicate that the aptamer A10-2 might be developed into one molecular probe to detect HCC from normal liver specimens.

Apoptin-modified human mesenchymal stem cells inhibit growth of lung carcinoma in nude mice.

Human mesenchymal stem cells (MSCs) represent a novel carrier for gene therapy and apoptin is a potential tumor-selective apoptosis-inducing protein. In the present study, the anti-tumoral effect of MSCs modified with apoptin against lung carcinoma was evaluated. Apoptin protein was expressed in a prokaryotic expression system and purified by affinity chromatography. Subsequently, anti-apoptin antibody was prepared by immunizing BALB/c mice with purified apoptin protein. Human MSCs were isolated, amplified and transduced with lentiviral vectors encoding full-length apoptin, in which the secretory signal and protein transduction sequence were added into the amino terminus to assist apoptin in entering into target cells. The differentiation and apoptin expression of apoptin-modified MSCs were confirmed. Subsequently, the anti-tumor effect of apoptin-modified MSCs was measured in vitro and in vivo. Following modification with apoptin, MSCs retained their differentiation capacity, and successfully synthesized and secreted apoptin, which entered target cells and selectively induced lung cancer cell apoptosis through activating caspase-3. The percentage of tumor cells with activated caspase-3 in the apoptin-modified MSCs group was markedly higher than that in the MSCs group (16.5 ± 2.9% at 24 h and 27.3 ± 2.0% at 48 h vs. 3.4 ± 1.1% at 24 h and 2.2 ± 0.6% at 48 h). When injected into nude mice, apoptin-modified MSCs inhibited the growth of lung carcinoma compared with that in the control groups (0.14 ± 0.02 g vs. 0.21 ± 0.04 g vs. 0.31 ± 0.05 g, P < 0.05). The results of the present study provided preclinical support of apoptin­based cancer therapy with MSCs as cellular vehicles.

[Preparation of anti-Golgi protein 73 polyclonal antibodies and establishment of particle-enhanced turbidimetric immunoassay for Golgi protein 73].

OBJECTIVE: To prepare the polyclonal antibodies against Golgi protein 73 (GP73) and preliminarily establish the particle-enhanced turbidimetric immunoassay. METHODS: New Zealand rabbits were immunized with recombinant GP73 protein to obtain the polyclonal antibodies. The antibodies were purified and covalently attached to latex particles. Under the optimized reaction conditions, the covalent latex-antibody complexes were prepared to establish the GP73 particle-enhanced turbidimetric immunoassay. RESULTS: The titer of purified polyclonal antibodies reached 16 000. The best reaction conditions were that the concentration of EDAC/NHS was 10 mg/mL, the reaction solution was PBS (pH6), reaction time was 3 hours at room temperature. Under such conditions, the coupling efficiency was the highest. The particle-enhanced turbidimetric assay showed a good specificity and sensitivity with a good linear relationship in the range of 6.25-200 ng/mL. The determination limit was 10 ng/mL. CONCLUSION: The study has successfully purified anti-GP73 antibodies, prepared the covalent latex-antibody complexes and established particle-enhanced turbidimetric immunoassay.

IFN-γ-secreting-mesenchymal stem cells exert an antitumor effect in vivo via the TRAIL pathway.

Mesenchymal stem cells (MSCs) can exhibit either prooncogenic or antitumor properties depending on the context. Based on our previous study, we hypothesized that MSCs engineered to deliver IFN-γ would kill cancer cells through persistent activation of the TRAIL pathway. Human bone-marrow (BM-) derived MSCs were isolated, amplified, and transduced with a lentiviral vector encoding the IFN-γ gene under the control of the EF1α promoter. The IFN-γ-modified MSCs effectively secreted functional IFN-γ, which led to long-term expression of TRAIL. More importantly, the IFN-γ-modified MSCs selectively induced apoptosis in lung tumor cells through caspase-3 activation within the target cells. The percentage of activated-caspase-3-positive tumor cells in IFN-γ-modified MSCs cocultures was significantly higher than in control MSCs cocultures. Treatment with anti-TRAIL antibody dramatically suppressed the caspase-3 activation observed in H460 cells. After injection into nude mice, the IFN-γ-modified MSCs inhibited the growth and progression of lung carcinoma compared with control cells. Collectively, our results provide a new strategy for tumor therapy that utilizes IFN-γ-modified MSCs.

[Expression and purification of recombinant Trail protein in E.coli and the optimal conditions for Trail purification].

AIM: To construct the expression vector pET-28α-Trail(114-281); and find the optimal conditions for target gene expression, host bacteria lysis, and protein purification, and to detect the apoptosis function of the recombinant protein. METHODS: The functional domain of Trail(114-281); was amplified by PCR and cloned into the expression vector pET-28α(+). After confirmed by DNA sequencing, the Trail(114-281); was expressed in E.coli BL21 under the condition of different A(600);, IPTG concentration and temperature. Host bacteria were lysed using three different ways, including ultrasonication, osmotic shock and IP lysis, and the target protein was purified using Ni-NTA affinity chromatography or cutting-gel purification. The advantages and shortcomings of these methods were compared to find the most efficient ways for expression and purification of the recombinant protein. The immunocompetence of Trail protein from cutting-gel purification was analyzed by Western blotting, A549 cell apoptosis induced by purified protein from Ni-NTA chromatography was detected by flow cytometry. RESULTS: The 516 bp Trail(114-281); gene was cloned, and expressed in E.coli BL21. When A(600);=0.6, recombinant host bacteria were induced by 1.0 mmol/L IPTG at 37 DegreesCelsius for 4 h, which was the optimal condition for the expression of inclusion body, and the soluble protein was expressed stably on the condition of 25 DegreesCelsius, A(600);=1.0, IPTG1.0 mmol/L. Ultrasonication could get maximal protein compared to the other methods. The two purification ways both could purify taget protein successfully. Western blot analysis showed that the protein purified by cutting-gel has a good immunologic activity. Protein from Ni-NTA affinity chromatography caused cell apoptosis. CONCLUSION: The expression vector pET-28α-Trail(114-281); can be constructed and expressed in E.coli BL21 successfully. Temperature is a more important effect factor of Trail(114-281); expression in host bacteria compared with other factors. Cutting-gel protein has immunogenicity, and Ni-NTA protein could keep its function. These results provide a basis for the further functional research and application of Trail.

IFN-γ-primed human bone marrow mesenchymal stem cells induce tumor cell apoptosis in vitro via tumor necrosis factor-related apoptosis-inducing ligand.

Human mesenchymal stem cells hold promise as gene therapy vectors for delivery of various genes to solid tumors for either therapeutic or tumor-tracing purposes. However, whether Mesenchymal stem cells support or inhibit tumor growth remains unknown. Herein, we first observed that mesenchymal stem cells primed with IFN-γ selectively induced the death of tumor cell lines, but not normal cells. We further identified that IFN-γ-primed mesenchymal stem cells expressed tumor necrosis factor-related apoptosis-inducing ligand. Tumor-suppressive effect of IFN-γ-primed mesenchymal stem cells could be blocked by activity neutralization or expression reduction of tumor necrosis factor-related apoptosis-inducing ligand. Moreover, mesenchymal stem cells mediated apoptosis of tumor cells by activating caspase-3 in such cells, via a mechanism involving tumor necrosis factor-related apoptosis-inducing ligand. However, when IFN-γ-primed or non-primed mesenchymal stem cells were co-injected into nude mice along with H460 cells, tumor growth was much faster than that of the group receiving only tumor cells (p<0.01) because of the promoting vascularization effect of mesenchymal stem cells, although IFN-γ-primed mesenchymal stem cells also exerted a certain degree of tumor-suppressive effect compared with non-primed cells (2.79±0.9 g versus 2.03±0.6 g). Collectively, our findings show that IFN-γ-primed human mesenchymal stem cells could induce cancer cell apoptosis via TRAIL-mediated pathway. In addition, our data afford a novel explanation of the opposing effects of hMSCs presence on tumor growth in vitro and in vivo. Thus, more attention needs to be paid when seeking to exploit mesenchymal stem cells as a therapeutic option under the condition of malignant tumor.

New insights on macrophage migration inhibitory factor: based on molecular and functional analysis of its homologue of Chinese amphioxus.

Macrophage migration inhibitory factor (MIF) is an intricate cytokine. Many questions about it are not fully resolved. In order to identify the role of MIF in Chinese amphioxus, its genomic organization, transcription pattern and enzymatic activity were studied. It's found that MIF has multi-copy gene number in the Chinese amphioxus genome and special transcription pattern in reproductive organs. Interestingly, the recombinant Bbt-MIF has tantomerase and redox activity, but fails to utilize GSH to reduce insulin instead of DTT, strikingly different from MIF in mammalian. All these results indicate that MIF gene must have undergone important changes in structure and function during the transition of invertebrate/vertebrate and might exert important role in this primitive species, which may be quite different from those found in vertebrate.

Genes "waiting" for recruitment by the adaptive immune system: the insights from amphioxus.

In seeking evidence of the existence of adaptive immune system (AIS) in ancient chordate, cDNA clones of six libraries from a protochordate, the Chinese amphioxus, were sequenced. Although the key molecules such as TCR, MHC, Ig, and RAG in AIS have not been identified from our database, we demonstrated in this study the extensive molecular evidence for the presence of genes homologous to many genes that are involved in AIS directly or indirectly, including some of which may represent the putative precursors of vertebrate AIS-related genes. The comparative analyses of these genes in different model organisms revealed the different fates of these genes during evolution. Their gene expression pattern suggested that the primitive digestive system is the pivotal place of the origin and evolution of the AIS. Our studies support the general statement that AIS appears after the jawless/jawed vertebrate split. However our study further reveals the fact that AIS is in its twilight in amphioxus and the evolution of the molecules in amphioxus are waiting for recruitment by the emergence of AIS.

Macrophage migration inhibitory factor (MIF) in chinese amphioxus as a molecular marker of immune evolution during the transition of invertebrate/vertebrate.

Macrophage migration inhibitory factor (MIF) is an important cytokine related to host defenses and autoimmune diseases. Here, we reported two full-length cDNA clones isolated from Chinese amphioxus (Branchiostoma belcheri tsingtaunese). Amino acid sequences analysis and structure prediction of these two molecules, called Bbt-MIF-I and Bbt-MIF-II, respectively, indicated that several conservative domains existed in the two amphioxus MIFs and their sequences were highly homologous to their counterparts of other species. Intriguingly, the Bbt-MIFs gene is present in multi-copy per haploid genome, which is very unusual compared with vertebrate's MIF gene given the known genome duplication theory. The genomic copy number, expression pattern of MIF gene and phylogenetic analysis of MIF proteins all suggested that a leap forward happened for MIF gene during the evolution from invertebrate to vertebrate. Considering the crucial role of MIF in innate immunity, MIF might serve as one of key molecular markers of evolution of immune system.

Molecular profile of the unique species of traditional Chinese medicine, Chinese seahorse (Hippocampus kuda Bleeker).

A cDNA library of male Chinese seahorse (Hippocampus kuda Bleeker) was constructed to investigate the molecular profile of seahorse as one of the most famous traditional Chinese medicine materials, and to reveal immunological and physiological mechanisms of seahorse as one of the most primitive vertebrates at molecular level. A total of 3372 expressed sequence tags (ESTs) consisting of 1911 unique genes (345 clusters and 1566 singletons) were examined in the present study. Identification of the genes related to immune system, paternal brooding and physiological regulation provides not only valuable insights into the molecular mechanism of immune system in teleost fish but also plausible explanations for pharmacological activities of Chinese seahorse. Furthermore, the occurrence of high prevalent C-type lectins suggested that a lectin-complement pathway might exert a more dominant function in the innate immune system of teleost than mammal. Carbohydrate recognition domain (CRD) without a collagen-like region in the lectins of seahorse was likely an ancient characteristic of lectins similar to invertebrates.

EST analysis of mRNAs expressed in neurula of Chinese amphioxus.

Amphioxus, a cephalochordate, is the closest living relative to the vertebrates. In order to investigate the molecular mechanisms of the early embryogenesis of amphioxus, we constructed a neurula embryo cDNA library of Chinese amphioxus (Branchiostoma belcheri tsingtauense) and generated 5235 expressed sequenced tags in the present study. The initial ESTs consisted of 638 clusters and 1855 singletons, which revealed approximately 2493 unique genes in the data set. Of these sequences, 35.52% ESTs matched to known genes, 12.76% matched to other ESTs, and 51.71% had no match to any known sequences in GenBank. Interestingly we found homologous genes related to neural development and human disease. Bioinformatic analysis showed the direct evidence that the gene homologue found only in vertebrates in previous studies also exists in the amphioxus genome. This study provides a preliminary view of the gene information involved in the development of neurula embryos of Chinese amphioxus and helps our understanding of vertebrate evolution at gene level.