HO-1-induced autophagy establishes a HO-1-p62-Nrf2 positive feedback loop to reduce gut permeability in cholestatic liver disease.

OBJECTIVES: The gut-liver axis disruption is a unified pathogenetic principle of cholestatic liver disease (CSLD). Increased gut permeability is the leading cause of gut-liver axis disruption. HO-1 is capable of protecting against gut-liver axis injury. However, it has rarely been reported whether autophagy is involved in HO-1 protecting gut-liver barrier integrity and the underlying mechanism. MATERIALS AND METHODS: Mice underwent bile duct ligation (BDL) was established as CSLD model in vivo. Caco-2 cells with LPS treatment was established as in vitro cell model. Immunofluorescence, western blot and transepithelial electrical resistance (TER) assay were used to observe epithelial tight junction (TJ) and autophagy. Liver injury and fibrosis were evaluated as well through H&E staining, masson staining, sirius red staining and ELISA. RESULTS AND CONCLUSIONS: Our study demonstrated that the epithelial TJ and TER were notably reduced both in BDL mice and in LPS treated intestinal epithelial cells. Increased HO-1 expression could significantly induce intestinal epithelial cell autophagy. Additionally, this increased autophagy level reversed the reduction effects of BDL or LPS on epithelial TJ and TER in vivo and in vitro, therefore decreased transaminase level in serum and relieved liver fibrosis in BDL mice. Besides, increased autophagy level in turn upregulated the expression of HO-1 by p62 degradation of Keap1 and subsequent activation of Nrf2 pathway. Collectively, these results indicate that HO-1 reduces gut permeability by enhancing autophagy level in CSLD, the increased autophagy establishes a HO-1-p62-Nrf2 positive feedback loop to further improve gut-liver axis disruption. Therefore, our study confirms the critical role of autophagy in HO-1 ameliorating gut-liver axis injury during CSLD, highlighting HO-1 as a promising therapeutic target.

Potent Neutralization of SARS-CoV-2 by Hetero-bivalent Alpaca Nanobodies Targeting the Spike Receptor-Binding Domain.

Cell entry by SARS-CoV-2 requires the binding between the receptor-binding domain (RBD) of the viral Spike protein and the cellular angiotensin-converting enzyme 2 (ACE2). As such, RBD has become the major target for vaccine development, while RBD-specific antibodies are pursued as therapeutics. Here, we report the development and characterization of SARS-CoV-2 RBD-specific VHH/nanobody (Nb) from immunized alpacas. Seven RBD-specific Nbs with high stability were identified using phage display. They bind to SARS-CoV-2 RBD with affinity KD ranging from 2.6 to 113 nM, and six of them can block RBD-ACE2 interaction. The fusion of the Nbs with IgG1 Fc resulted in homodimers with greatly improved RBD-binding affinities (KD ranging from 72.7 pM to 4.5 nM) and nanomolar RBD-ACE2 blocking abilities. Furthermore, the fusion of two Nbs with non-overlapping epitopes resulted in hetero-bivalent Nbs, namely aRBD-2-5 and aRBD-2-7, with significantly higher RBD binding affinities (KD of 59.2 pM and 0.25 nM) and greatly enhanced SARS-CoV-2 neutralizing potency. The 50% neutralization dose (ND50) of aRBD-2-5 and aRBD-2-7 was 1.22 ng/mL (∼0.043 nM) and 3.18 ng/mL (∼0.111 nM), respectively. These high-affinity SARS-CoV-2 blocking Nbs could be further developed into therapeutics as well as diagnostic reagents for COVID-19.ImportanceTo date, SARS-CoV-2 has caused tremendous loss of human life and economic output worldwide. Although a few COVID-19 vaccines have been approved in several countries, the development of effective therapeutics, including SARS-CoV-2 targeting antibodies, remains critical. Due to their small size (13-15 kDa), high solubility, and stability, Nbs are particularly well suited for pulmonary delivery and more amenable to engineer into multivalent formats than the conventional antibody. Here, we report a series of new anti-SARS-CoV-2 Nbs isolated from immunized alpaca and two engineered hetero-bivalent Nbs. These potent neutralizing Nbs showed promise as potential therapeutics against COVID-19.

Protective effect of the stressed supernatant from Lactococcus lactis subsp. lactis and its metabolic analysis.

There are numerous factors restricting wide application of lactic acid bacteria (LAB) in dairy industry, causing urgent demands for novel bioprotectants. Protective effects and metabolites of Lactococcus lactis subsp. lactis (L. lactis) from ultraviolet (UV)-induced supernatant were investigated and the protective mechanism was explored. The strain viability of the group treated with the supernatant of continuous UV irradiation (V1) and the group with intermittent UV irradiation (V2) was 8.45 and 14.13 times of the control group, respectively. Further exploration on the protective of L. lactis supernatant, under different dose of UV treatment, showed it was dose-dependent. The condition for the supernatant with best protective effect was vertical distance 50.00 cm, horizontal distance 25.00 cm, intermittent UV irradiation (30 s interval 30 s) for 4.5 min (V2), which was chose for untargeted metabolite analysis. And that in V1 was for comparative study. There were 181 up-regulated metabolites in V1 and 161 up-regulated metabolites in V2, respectively. Most of the up-regulated metabolites were related to secondary metabolite synthesis, environmental microbial metabolism, antibiotic synthesis and amino acid biosynthesis. Notably, production of dithiothreitol (DTT) in V2 was 65.2-fold higher than that in the control group. Trehalose in ABC transporter pathway was also up-regulated in the metabolites induced by UV. Results indicated that L. lactis could adapt to the UV stress by adjusting metabolic pathways and producing special metabolites to protect itself. This research offers the basis for robust strain development and contributes to initial study on potential bioprotectant.

Electroacupuncture Ameliorates Intestinal Barrier Destruction in Mice With Bile Duct Ligation-Induced Liver Injury by Activating the Cholinergic Anti-Inflammatory Pathway.

OBJECTIVES: Electroacupuncture (EA) at Zusanli (ST36) can attenuate inflammation in different rodent models. However, the therapeutic mechanisms underlying its action in inhibiting intestinal barrier destruction and liver injury in cholestasis mice have not been clarified. This study aimed at investigating whether EA at ST36 could activate the cholinergic anti-inflammatory pathway to inhibit intestinal barrier destruction and liver injury in cholestasis mice. MATERIALS AND METHODS: Male Hmox1floxp/floxp C57BL/6 mice were randomized and subjected to a sham or bile duct ligation (BDL) surgery. The BDL mice were randomized and treated with, or without (BDL group), sham EA at ST36 (BDL+sham-ST36) or EA at ST36 (BDL+ST36), or received α-bungarotoxin (α-BGT), a specific inhibitor of nicotinic acetylcholine receptor α7 subunit (α7nAChR), before stimulation (BDL+ST36+α-BGT). These mice, together with a group of intestine-specific heme oxygenase-1 (HO-1) knockout (KO) Villin-Cre-HO-1-/- mice, were monitored for their body weights before and 14 days after BDL. The levels of plasma cytokines and liver injury-related alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured by enzyme-linked immunoassay, and pathological changes in the intestinal mucosa and liver fibrosis as well as intestinal barrier permeability in individual mice were examined by histology and immunohistochemistry. The levels of α7nAChR, HO-1, ZO-1, Occludin, Claudin-1, and NF-κBp65 expression and NF-κBp65 phosphorylation in intestinal tissues were quantified. RESULTS: Compared with the sham group, BDL significantly increased the levels of plasma interleukin (IL)-1ß, IL-6, IL-10, tumor necrosis factor α, ALT, and AST and caused intestinal mucosal damages, high permeability, and liver fibrosis in mice, which were remarkably mitigated, except for further increased levels of plasma IL-10 in the BDL+ST36 group of mice. Similarly, EA at ST36 significantly up-regulated α7nAChR and HO-1 expression; mitigated the BDL-decreased ZO-1, Occludin, and Claudin-1 expression; and attenuated the BDL-increased NF-κBp65 phosphorylation in intestinal tissues of mice. The therapeutic effects of EA at ST36 were significantly abrogated by pretreatment with α-BGT or HO-1 KO. CONCLUSION: EA at ST36 inhibits the BDL-induced intestinal mucosal damage and liver fibrosis by activating the HO-1 cholinergic anti-inflammatory pathway in intestinal tissues of mice.

Plasma TIGIT Level Is a Possible Marker in HIV-Related Liver Damage.

T cell immunoglobulin and ITIM domain (TIGIT), has a key role in immunopathogenesis of HIV. Previous studies on immune checkpoint receptors had mainly focused on the membrane form. To evaluate clinical significance of soluble form of TIGIT (sTIGIT) in people living with HIV. Blood samples of 61 untreated HIV-infected patients and 24 healthy individuals were collected and TIGIT concentrations in plasma were measured by ELISA method. A decreased level of plasma TIGIT in HIV-infected patients was found to be negatively associated with AST/ALT ratio (r = -0.5358, p = 0.0483) that was indicative of liver damage. Moreover, the proportion of TIGIT on CD3+CD4+ cells in HIV-infected individuals increased (47.12 ± 5.051%) compared with in healthy controls (22.13 ± 4.426%, p < 0.01), which indicated change in plasma TIGIT level was at least partially attributed to CD3+CD4+ T cells. Furthermore, there was a strong positive correlation between TIGIT plasma levels and lymphocyte activation gene-3 (LAG-3) plasma levels in HIV-infected patients with a linear correlation coefficient r = 0.904. Therefore, plasma TIGIT level is a possible marker in HIV-related liver damage and LAG-3 closely related to TIGIT possibly plays a co-ordinated role in HIV-related liver damage.

60Coγ induction improves the protective effect of Acetobacter pasteurianus against ionizing radiation in mice.

Exposure to ionizing radiation (IR) tends to cause serious health concerns. Thus, radioprotective agents are vital for the population exposed to radiation. As microorganisms have the advantages of fast reproduction and no geographical restrictions, direct microbe-based and environmental induction compounds are thriving radioprotectants resources. Oxidative system and oxidase in Acetobacter pasteurianus are unique and intriguing, the radioprotective effect of the cell-free extract from A. pasteurianus (APE) and 60Coγ-treated extract (IRE) were comparatively investigated in the present study. The survival rate of A. pasteurianus with IRE addition was 149.1% in H2O2 damage test, while that with APE was only 10.4%. The viability of 60Coγ-treated AML-12 cells was increased by 18.8% with IRE addition, yet APE showed no significant radioprotective effect. Moreover, in 60Coγ-treated mice, IRE could significantly protect the white blood cell, improve the liver index, and attenuate the injuries of immune organs in mice. Administration of IRE significantly raised the activities of superoxide dismutase (SOD) and reduced the products of lipid peroxidation. These results clarified that gavage with APE and IRE presented notable antioxidant and radioprotective efficacy. A. pasteurianus showed appealing potential to be novel radioprotective bioagents and 60Coγ treatment on microbe could be a new method for the development of better radioprotectant. KEY POINTS: • 60Coγ induction could improve the radioprotective effect of APE. • IRE protected white blood cell in mice under IR. • IRE products have broad application prospects in radioprotection based on microbes.

Biochemical characterization of SARS-CoV-2 nucleocapsid protein.

The nucleocapsid (N) protein is an important antigen for coronavirus, which participate in RNA package and virus particle release. In this study, we expressed the N protein of SARS-CoV-2 and characterized its biochemical properties. Static light scattering, size exclusive chromatography, and small-angle X-ray scattering (SAXS) showed that the purified N protein is largely a dimer in solution. CD spectra showed that it has a high percentage of disordered region at room temperature while it was best structured at 55 °C, suggesting its structural dynamics. Fluorescence polarization assay showed it has non-specific nucleic acid binding capability, which raised a concern in using it as a diagnostic marker. Immunoblot assays confirmed the presence of IgA, IgM and IgG antibodies against N antigen in COVID-19 infection patients' sera, proving the importance of this antigen in host immunity and diagnostics.

Quantitative proteomic analysis reveals that Luks-PV exerts antitumor activity by regulating the key proteins and metabolic pathways in HepG2 cells.

Hepatocellular carcinoma (HCC) is a complicated and poor prognosis cancer, necessitating the development of a potential treatment strategy. In this study, we initially revealed that LukS-PV belonged to leukocidin family performs an anti-HCC action. Then, we used liquid chromatography-mass spectrometry (LC/MS) to compare protein expression profiles of the LukS-PV-treated human HCC cell lines HepG2 and the control cells. GO annotations and Kyoto Encyclopedia of Genes and Genomes pathway analysis were carried out of differential expression followed by protein-protein interactome, to explore the underlying cancer suppressor mechanisms of LukS-PV for human HCC. A total of 88 upregulated proteins and 46 downregulated proteins were identified. The top 10 proteins identified by the MCC method are FN1, APP, TIMP1, nucleobindin-1, GOLM1, APLP2, CYR61, CD63, ENG, and CD9. Our observation on protein expression indicated that LukS-PV produces a signature affecting central carbon metabolism in cancer, galactose metabolism, and fructose and mannose metabolism pathways. The results give a functional effects and molecular mechanism insight, following LukS-PV treatment.

Isolation and identification of hyper-ammonia-producing bacteria from commercial fermented skates (Raja kenojei).

Ammonia-producing bacteria were isolated and identified from five commercial fermented skates (A1, A2, A3, A4, and A5). In addition, the pH, ammonia nitrogen, total volatile nitrogen (TVBN), trimethylamine nitrogen (TMAN), and amino nitrogen contents of skate samples were also determined. A total of 88 strains of ammonia-producing bacteria was isolated and seven hyper-ammonia-producing bacteria isolates (A2-2, A2-3, A2-12, A2-18, A2-20, A3-6 and A3-14) were selected based on ammonia nitrogen producing ability. Those isolates were identified as Proteus hauseri (three strains), Providencia rustigianii (three strains), and Kurthia gibsonii. The pH and ammonia nitrogen content in skate samples were ranged from 8.63 to 9.03, and 4.86 to 7.31 g/kg, respectively. No significant difference of pH values was observed in skate samples A2, A3, A4 and A5. While, skate samples A3, A4 and A5 showed similar level of TVBN and TMAN content. Skate sample A2 showed the highest amino nitrogen content among all samples, which indicated the highest degree of protein degradation of skate muscle during fermentation. Bivariate cluster analysis showed that skate samples A3, A4, and A5 clustered together at a relatively high level, implying a similar microbial environment during fermentation. The cluster analysis allowed different commercial fermented skates to be clearly differentiated based on the characteristics determined in this study. This study can provide important information for investigating the mechanisms underlying ammonia flavor formation in skate muscle during fermentation.

VraR Binding to the Promoter Region of agr Inhibits Its Function in Vancomycin-Intermediate Staphylococcus aureus (VISA) and Heterogeneous VISA.

Acquisition of vancomycin resistance in Staphylococcus aureus is often accompanied by a reduction in virulence, but the mechanisms underlying this change remain unclear. The present study was undertaken to investigate this process in a clinical heterogeneous vancomycin-intermediate S. aureus (hVISA) strain, 10827; an hVISA reference strain, Mu3; and a VISA reference strain, Mu50, along with their respective series of vancomycin-induced resistant strains. In these strains, increasing MICs of vancomycin were associated with increased expression of the vancomycin resistance-associated regulator gene (vraR) and decreased expression of virulence genes (hla, hlb, and coa) and virulence-regulated genes (RNAIII, agrA, and saeR). These results suggested that VraR might have a direct or indirect effect on virulence in S. aureus In electrophoretic mobility shift assays, VraR did not bind to promoter sequences of hla, hlb, and coa genes, but it did bind to the agr promoter region. In DNase I footprinting assays, VraR protected a 15-nucleotide (nt) sequence in the intergenic region between the agr P2 and P3 promoters. These results indicated that when S. aureus is subject to induction by vancomycin, expression of vraR is upregulated, and VraR binding inhibits the function of the Agr quorum-sensing system, causing reductions in the virulence of VISA/hVISA strains. Our results suggested that VraR in S. aureus is involved not only in the regulation of vancomycin resistance but also in the regulation of virulence.

INVESTIGATION ON CRYPTOSPORIDIUM INFECTIONS IN WILD ANIMALS IN A ZOO IN ANHUI PROVINCE.

To assess Cryptosporidium infections among wild animals in a zoo located in Anhui province, we conducted an investigation on the fecal samples collected from 44 primates, 41 herbivores, 44 carnivores and omnivores, and 103 birds in the zoo with the use of Sheather's sugar flotation technique and modified acid-fast staining. Cryptosporidium oocysts were detected in the fecal samples from six primates, two herbivores, four carnivores and omnivores, and seven birds by using Sheather's sugar flotation technique; the prevalence of Cryptosporidium infection in primates, herbivores, carnivores and omnivores and birds was 13.64, 4.88, 9.09, and 6.80%, respectively. Modified acid-fast staining detected the presence of Cryptosporidium oocysts in the fecal samples of one primate, three herbivores, 0 carnivores and omnivores, and one bird, and the prevalence of Cryptosporidium infection in primates, herbivores, carnivores and omnivores and birds was 2.27, 7.32, 0.00, and 0.97%, respectively. Polymerase chain reaction-restriction fragment-length polymorphism (PCR-RFLP) and phylogenetic analysis with the use of the neighbor-joining (NJ) method based on the aligned partial small-subunit (SSU) rRNA gene sequences showed that the protozoan pathogen isolated from primates was Cryptosporidium hominis and the pathogen isolated from camels ( Camelus dromedarius ) was Cryptosporidium andersoni. Subtyping the Cryptosporidium hominis by 60-kDa glycoprotein (GP60) gene phylogenetic analysis showed the Cryptosporidium hominis belongs to the subtype IdA and IbA.

[Morphological Characteristics and Molecular Identification of Trichuris sp. from Giraffe].

Objective: To investigate the morphological characteristics of Trichuris sp. from giraffe in Hefei wild zoo and identify its species using molecular techniques. Methods: Morphological characteristics of Trichuris collected from giraffe were analyzed. The internal transcribed spacer 1（ITS-1） was amplified by PCR and the PCR product was sequenced. The resulting sequence was homology analysis in GenBank and its heredity evolution tree was constructed by MEGA 4.0 software. Results: The male worms had a body length of 35.89-58.56 mm, an esophagus to body length ration of 0.29-0.40, and a spicule length of 1.96-3.89 mm. The thick and thin proportions of body were 7.02-23.45 mm and 28.05-40.05 mm respectively. These data showed different degrees of variation with previous reports. The PCR resulted in a product of 491 bp, comprising part of 18S rRNA and full length ITS-1. Sequence alignment showed that the identified Trichuris was most homologous（98.6%） with T. bos taurus HE608848, T. capreolus JX218218, and T. japanese AB367795, but it was only 46.0% homologous with T. discolor AB367794. In the heredity evolution tree, it was not located on the same branch as T. discolor, T. ovis and T. bos taurus. Conclusions: The Trichuris sp. collected from giraffe is different from previous reports in morphology and ITS-1 sequence. Further research is needed to determine if it is a new species.

[Establishment of LAMP Detection for Toxoplasma gondii Based on the 529 bp Repeat Sequence].

Objective: To establish the loop mediated isothermal amplification（LAMP） technique for determining Toxoplama gondii. Methods: The primers for LAMP of the conserved 529 bp sequence was designed by the Primer Explorer 4.0 software. The LAMP reaction was made on the constructed pMD-19T-529 bp recombinant plasmid as a template, and was optimized in loop primer, concentrations of betaine and MgSO4, and reaction temperature. The optimized LAMP and PCR were performed in ultra-pure water, on pig genome, Cryptosporidium parvum genome, Isospora suis genome, and pMD-19T-529 bp, respectively, to test the sensitivity of LAMP. The pMD-19T-529 bp was serially diluted to 109-100 copies/ml to test the specificity of LAMP. Results: LAMP using the designed primers amplified the 529 bp fragment of T. gondii. The optimized LAMP system had a total reaction volume of 25 µl, with the optimal concentrations of betaine and MgSO4 being 0.4 mol/L and 6 mmol/L, respectively. The amplification efficiency of 30 min reaction in the presence of loop primer was comparable to that of 60 min reaction without loop primer, which indicated that addition of loop primer shortened the reaction time by 30 min. The optimal reaction condition was 63 ℃ 30 min, 80 ℃ 3 min. The established LAMP method specifically amplifed the 529 bp fragment of T. gondii, and its efficiency was 10 times of PCR（detection threshold 103 copies/ml vs. 104 copies/ml）. Conclusion: The established LAMP for detecting Toxoplama gondii 529 bp repeat sequence shows high specificity and sensitivity.

Nuclear factor E2-related factor-2 (Nrf2) is required for NLRP3 and AIM2 inflammasome activation.

Despite the number of extensive studies on the immune function and signaling of inflammasomes in various diseases, the activating mechanism of inflammasome, especially the NLRP3 inflammasome, is not fully understood. Nuclear factor E2-related Factor-2 (Nrf2), a key transcription factor that regulates cellular redox homeostasis, has been reported to play both protective and pathogenic roles depending on the disease conditions through undefined mechanism. This study reveals an essential role of Nrf2 in inflammasome activation. LPS stimulation increased Nrf2 protein levels in a Myd88-dependent manner. When compared with wild-type controls, Nrf2-deficient (Nrf2(-/-)) macrophages showed decreased maturation and secretion of caspase-1 and IL-1ß and reduced apoptosis-associated speck-like protein containing CARD (ASC) speck formation in response to various NLRP3 and AIM2 inflammasome stimuli. In contrast, NLRC4 inflammasome activation was not controlled by Nrf2. Biochemical analysis revealed that Nrf2 appeared in the ASC-enriched cytosolic compartment after NLRP3 inflammasome activation. Furthermore, mitochondrial reactive oxygen species-induced NLRP3 activation also required Nrf2. Nrf2(-/-) mice showed a dramatic decrease in immune cell recruitment and IL-1ß generation in alum-induced peritonitis, which is a typical IL-1 signaling-dependent inflammation animal model. This work discovered a critical proinflammatory effect of Nrf2 by mediating inflammasome activation.

Investigating the effects of low-salt processing on the umami peptides of dry-cured ham using peptidomics techniques.

This study investigated the effect of low-salt processing on the umami peptide profile of dry-cured hams. Peptidomics data showed 633 umami peptides in the low- and full-salt groups. Among them, 36.2% and 26.5% of shared umami peptides in the low-salt group were significantly down- and up-regulated in relative abundance. Multivariate statistical analysis showed 1011 significantly different umami peptides (SDUPs) in the low- and full-salt groups. Creatine kinase M-type (CKM) and fast skeletal muscle troponin T (TnTf) were the main precursor proteins of these SDUPs. At the end of processing, the relative expression of CKM was lower in the low-salt group than in the full-salt group (P < 0.05), but there was no significant difference in TnTf. More dipeptidyl peptidase cleavage sites were observed in CKM and TnTf proteins in the low-salt group.

Biyang floral mushroom-derived exosome-like nanovesicles: characterization, absorption stability and ionizing radiation protection.

Diet-derived exosome-like nanovesicles are a class of natural active substances that have similar structures and functions to mammalian exosomes. Biyang floral mushrooms and their active extracts have been found to possess radioprotective effects and to deeply explore their novel active substances, the radioprotective effects of Biyang floral mushroom-derived exosome-like nanovesicles (BFMELNs) were investigated in this study. Results showed that these surface-negatively charged vesicles possessed an ideal size and good stability against environmental changes such as temperature and gastrointestinal digestion. Furthermore, BFMELNs could effectively be taken up by HL-7702 cells and Caco-2 cells through cellular phagocytosis mediated by clathrin and dynein. Emphatically, BFMELNs with an exosome-like morphology contained RNA, proteins, lipids, polyphenols and flavonoids to exert good antioxidant and radioprotective effects in vitro. Meanwhile, BFMELNs also exhibited good radioprotective effects by restoring peripheral blood indexes, mitigating damage to organs, and regulating the redox state in mice. Collectively, BFMELNs showed promise as novel and natural radioprotective nano-agents for preventing IR-induced oxidative stress damage.

Exploring the novel antioxidant peptides in low-salt dry-cured ham: Preparation, purification, identification and molecular docking.

Dry-cured ham is important source of bioactive peptides. In this study, the antioxidant activities of peptides and components from low and fully salted dry-cured hams were compared by peptidomics. And novel antioxidant peptides were identified and characterized. The results showed that the peptides (<3 KDa) extracted from low-salt dry-cured ham had higher antioxidant activity. Therefore, the antioxidant peptides in low-salt dry-cured ham were further characterized and the mechanism of their antioxidant activity was investigated. From the five candidate peptides selected, we found DWPDARGIWHND (DD12) to be highly stable, non-sensitizing, and non-toxic with the highest free radical scavenging activity. Molecular docking predicted that DD12 interacted with Keap1 through hydrogen-bond formation and hydrophobic interactions, suggesting that DD12 had good cellular antioxidant activity. DD12 peptide can bind to DPPH• and ABTS•+, resulting in strong free radical scavenging activity. Our findings support the development and application of natural antioxidant peptides in dry-cured ham.

Circulating IL-21 levels increase during early simian-human immunodeficiency virus infection in macaques.

The cytokine interleukin-21 (IL-21) regulates viral pathogenesis in individuals infected with human and simian immunodeficiency viruses. However, because the time of initial infection with HIV in humans is rarely known, the dynamics of IL-21 production during the first weeks have not been adequately explored. In the present study, we used rhesus macaques to model the first stages of infection. Twenty-two rhesus macaques were infected rectally with simian-human immunodeficiency virus (SHIV)-1157ipd3N4, and for 12 weeks, replication of the virus, the numbers of CD4+ and CD8+ T cells, and the levels of plasma IL-21 were monitored. Our study demonstrated that plasma levels of IL-21 increased during the early phase of SHIV infection when compared with the values observed before inoculation. We conclude that IL-21 has a likely role in the immunopathogenesis of HIV/SIV/SHIV.

Correction to: Bioactive compounds and antioxidant activities of Quercus salicina Blume extract.

[This corrects the article DOI: 10.1007/s10068-020-00755-1.].