Synthesis of Tetrasubstituted Alkenes by Rhodium-Catalyzed Regioselective Cyano Transfer.

We describe herein a novel, general, and robust approach to structurally diversified alkenyl nitriles through a Rh-catalyzed cyano transfer reaction between alkynyl-malononitrile derivatives and aryl/alkenyl boronic acids. This reaction exhibits high chemo- and regioselectivity and a broad substrate scope. The tetrasubstituted alkenyl dinitriles (34 examples, average 58% yield) are obtained through substrate tuning and ligand control.

Investigating the Role of KLF6 in the Growth of Bovine Preadipocytes: Using Transcriptomic Analyses to Understand Beef Quality.

Intramuscular fat is a crucial determinant of carcass quality traits like tenderness and taste, which in turn is influenced by the proliferation of intramuscular preadipocytes. This study aimed to investigate the Krüppel-like factor 6 (KLF6)-mediated proliferation of bovine preadipocytes and identify underlying molecular mechanisms. Down-regulation of KLF6 by siKLF6 resulted in a significant (p < 0.01) suppression of cell cycle-related genes including CDK1, MCM6, ZNF4, PCNA, CDK2, CCNB1, and CDK6. Conversely, the expression level of p27 was significantly (p < 0.01) increased. Moreover, EdU (5-ethynyl-20-deoxyuridine) staining revealed a significant decrease in EdU-labeled cells due to KLF6 down-regulation. Collectively, these findings indicate that KLF6 down-regulation inhibits adipocyte proliferation. Furthermore, RNA sequencing of preadipocytes transfected with siKLF6 and NC, followed by differential gene expression analysis, identified 100 up-regulated and 70 down-regulated genes. Additionally, the differentially expressed genes also significantly influenced various Gene Ontology (GO) terms related to cell cycle, nuclear chromosomes, and catalytic activity on DNA. Furthermore, the top 20 pathways enriched in these DEGs included cell cycle, DNA replication, cellular senescence, and homologous recombination. These GO terms and KEGG pathways play key roles in bovine preadipocyte proliferation. In conclusion, the results of this study suggest that KLF6 positively regulates the proliferation of bovine preadipocytes.

Effect of Lactobacillus plantarum BFS1243 on a female frailty model induced by fecal microbiota transplantation in germ-free mice.

Frailty, a complex geriatric syndrome, significantly impedes the goal of achieving 'healthy aging'. Increasing evidence suggests a connection between gut microbiota, systemic inflammation, and disease. However, it remains to be determined whether interventions targeting the intestinal flora can effectively ameliorate frailty. Our research involved fecal microbiota transplantation (FMT) experiments on germ-free (GF) mice, dividing these mice into three groups: a group receiving transplants from healthy elderly individuals (HF group), a group of frailty patients (FF group), and the FF group supplemented with Lactobacillus plantarum BFS1243 (FFL group). Our findings indicated a significant shift in the gut microbiota of the FF group, in contrast to the HF group, characterized by decreased Akkermansia and increased Enterocloster, Parabacteroides, and Eisenbergiella. Concurrently, there was a reduction in amino acids and SCFAs, with BFS1243 partially mitigating these changes. The FF group exhibited an upregulation of inflammatory markers, including PGE2, CRP, and TNF-α, and a downregulation of irisin, all of which were moderated by BFS1243 treatment. Furthermore, BFS1243 improved intestinal barrier integrity and physical endurance in the FF mice. Correlation analysis revealed a negative association between SCFA-producing species and metabolites like lysine and butyric acid with pro-inflammatory factors. In conclusion, our study conclusively demonstrated that alterations in the gut microbiota of elderly individuals can lead to physical frailty, likely due to detrimental effects on the intestinal barrier and a pro-inflammatory state. These findings underscore the potential of gut microbiome modulation as a clinical strategy for treating frailty.

Advances in traditional herbal formulation based nano-vaccine for cancer immunotherapy: Unraveling the enigma of complex tumor environment and multidrug resistance.

Cancer is attributed to uncontrolled cell growth and is among the leading causes of death with no known effective treatment while complex tumor microenvironment (TME) and multidrug resistance (MDR) are major challenges for developing an effective therapeutic strategy. Advancement in cancer immunotherapy has been limited by the over-activation of the host immune response that ultimately affects healthy tissues or organs and leads to a feeble response of the patient's immune system against tumor cells. Besides, traditional herbal medicines (THM) have been well-known for their essential role in the treatment of cancer and are considered relatively safe due to their compatibility with the human body. Yet, poor solubility, low bio-availability, and lack of understanding about their pathophysiological mechanism halt their clinical application. Moreover, considering the complex TME and drug resistance, the most precarious and least discussed concerns for developing THM-based nano-vaccination, are identification of specific biomarkers for drug inhibitory protein and targeted delivery of bioactive ingredients of THM on the specific sites in tumor cells. The concept of THM-based nano-vaccination indicates immunomodulation of TME by THM-based bioactive adjuvants, exerting immunomodulatory effects, via targeted inhibition of key proteins involved in the metastasis of cancer. However, this concept is at its nascent stage and very few preclinical studies provided the evidence to support clinical translation. Therefore, we attempted to capsulize previously reported studies highlighting the role of THM-based nano-medicine in reducing the risk of MDR and combating complex tumor environments to provide a reference for future study design by discussing the challenges and opportunities for developing an effective and safe therapeutic strategy against cancer.

Interfacial crystallized oleogel emulsion with improved freeze-thaw stability and tribological properties: Influence of cooling rate.

In this study, the influence of cooling rate on the freeze-thaw stability, rheological and tribological properties of interfacial crystalized oleogel emulsion was investigated. Results showed that slower cooling rate could promote formation of larger crystals and stronger network in oleogels. Additionally, oleogel emulsions showed higher freeze-thaw stability than those stabilized solely by emulsifiers. The slower cooling rate resulted in larger crystals adsorbed at the droplet surface. This led to greater steric hindrance that prevented the migration of oil droplets with higher resistance to disruption by ice crystals. The rheological and tribological measurements suggested that with appropriate amount of crystals, the tribological properties were better maintained for emulsions prepared at slow cooling rate after freeze-thaw treatment. This strategy greatly enriched oleogel emulsion formulations and provided important clues for potential applications in food products involved with freeze-thaw treatment.

Hypersampsonone H attenuates ulcerative colitis via inhibition of PDE4 and regulation of cAMP/PKA/CREB signaling pathway.

BACKGROUND AND OBJECTIVES: Ulcerative colitis (UC) is a recurrent intestinal inflammatory disease which poses a serious threat to the life of patients. However, there are no specific drugs for UC yet. Hypericum sampsonii Hance (HS) is a Chinese herbal medicine traditionally used to treat enteritis and dysentery. Our previous studies have demonstrated that HS holds potential anti-UC effects, and a novel compound named Hypersampsonone H (HS-1) isolated from HS possesses significant anti-inflammatory activity. However, the beneficial effects of HS-1 on UC remain unclear. This study aimed to investigate the therapeutic effects of HS-1 on UC and its potential mechanisms, both in vitro and in vivo. METHODS: The in vitro model was employed using LPS-induced RAW264.7 cells to investigate the anti-inflammatory effects of HS-1 and its possible mechanisms. Furthermore, the therapeutic efficacy and potential mechanisms of HS-1 against dextran sulfate sodium (DSS)-induced acute colitis were assessed through histopathological examination, biochemical analysis, and molecular docking. RESULTS: In vitro, HS-1 significantly reduced LPS-induced inflammatory responses, as indicated by inhibiting NO production, down-regulating the overexpression of COX-2 and iNOS, as well as regulating the imbalanced levels of IL-6, TNF-α, and IL-10. Moreover, HS-1 also inhibited the expression of PDE4, elevated the intracellular cAMP level, and promoted the phosphorylation of CREB, thereby activating the PKA/CREB pathway in RAW264.7 cells. In vivo, HS-1 demonstrated therapeutic capacity against DSS-induced colitis by alleviating the symptoms of colitis mice, regulating the abnormal expression of inflammatory mediators, protecting the integrity of intestinal epithelial barrier, and reducing tissue fibrosis. Consistently, HS-1 was found to decrease the expression of PDE4 isoforms, subsequently activating the cAMP/PKA/CREB signaling pathway. Furthermore, the molecular docking results indicated that HS-1 exhibited a high affinity for PDE4, particularly PDE4D. Further mechanistic validation in vitro demonstrated that HS-1 possessed a synergistic effect on forskolin and an antagonistic effect on H-89 dihydrochloride, thereby exerting anti-inflammatory effects through the cAMP/PKA/CREB signaling pathway. CONCLUSION: We disclose that HS-1 serves as a promising candidate drug for the treatment of UC by virtue of its ability to reduce DSS-induced colitis via the inhibition of PDE4 and the activation of cAMP/PKA/CREB signaling pathway.

Improving quality of poultry and its meat products with probiotics, prebiotics, and phytoextracts.

Remarkable changes have occurred in poultry farming and meat processing in recent years, driven by advancements in breeding technology, feed processing technology, farming conditions, and management practices. The incorporation of probiotics, prebiotics, and phytoextracts has made significant contributions to the development of poultry meat products that promote both health and functionality throughout the growth phase and during meat processing. Poultry fed with these substances improve meat quality, while incorporating probiotics, prebiotics, and phytoextracts in poultry processing, as additives or supplements, inhibits pathogens and offers health benefits to consumers. However, it is vital to assess the safety of functional fermented meat products containing these compounds and their potential effects on consumer health. Currently, there's still uncertainty in these aspects. Additionally, research on utilizing next-generation probiotic strains and synergistic combinations of probiotics and prebiotics in poultry meat products is in its early stages. Therefore, further investigation is required to gain a comprehensive understanding of the beneficial effects and safety considerations of these substances in poultry meat products in the future. This review offered a comprehensive overview of the applications of probiotics and prebiotics in poultry farming, focusing on their effects on nutrient utilization, growth efficiency, and gut health. Furthermore, potential of probiotics, prebiotics, and phytoextracts in enhancing poultry meat production was explored for improved health benefits and functionality, and possible issues associated with the use of these substances were discussed. Moreover, the conclusions drawn from this review and potential future perspectives in this field are presented.

Advances of Predicting Allosteric Mechanisms Through Protein Contact in New Technologies and Their Application.

Allostery is an intriguing phenomenon wherein the binding activity of a biological macromolecule is modulated via non-canonical binding site, resulting in synchronized functional changes. The mechanics underlying allostery are relatively complex and this review is focused on common methodologies used to study allostery, such as X-ray crystallography, NMR spectroscopy, and HDXMS. Different methodological approaches are used to generate data in different scenarios. For example, X-ray crystallography provides high-resolution structural information, NMR spectroscopy offers dynamic insights into allosteric interactions in solution, and HDXMS provides information on protein dynamics. The residue transition state (RTS) approach has emerged as a critical tool in understanding the energetics and conformational changes associated with allosteric regulation. Allostery has significant implications in drug discovery, gene transcription, disease diagnosis, and enzyme catalysis. Enzymes' catalytic activity can be modulated by allosteric regulation, offering opportunities to develop novel therapeutic alternatives. Understanding allosteric mechanisms associated with infectious organisms like SARS-CoV and bacterial pathogens can aid in the development of new antiviral drugs and antibiotics. Allosteric mechanisms are crucial in the regulation of a variety of signal transduction and cell metabolism pathways, which in turn govern various cellular processes. Despite progress, challenges remain in identifying allosteric sites and characterizing their contribution to a variety of biological processes. Increased understanding of these mechanisms can help develop allosteric systems specifically designed to modulate key biological mechanisms, providing novel opportunities for the development of targeted therapeutics. Therefore, the current review aims to summarize common methodologies that are used to further our understanding of allosteric mechanisms. In conclusion, this review provides insights into the methodologies used for the study of allostery, its applications in in silico modeling, the mechanisms underlying antibody allostery, and the ongoing challenges and prospects in advancing our comprehension of this intriguing phenomenon.

Hypericum sampsonii Hance: a review of its botany, traditional uses, phytochemistry, biological activity, and safety.

Ethnopharmacological relevance: Hypericum sampsonii Hance, also known as Yuanbao Cao in Chinese, is a traditional medicinal herb from the Guttiferae family and has been widely used in China to treat various conditions, including dysentery, enteritis, mastitis, scrofula, and contusion. Aim of the review: This review aims to provide a comprehensive overview of the botany, traditional uses, phytochemistry, biological activity and safety of H. sampsonii and to highlight its potential for medical application and drug development. Materials and methods: We searched several databases, i.e., Web of Science, SciFinder, PubMed, CBM, CNKI, Google Scholar, etc., for relevant information on H. sampsonii. Additionally, we also consulted some books on Chinese medicine. Results: To date, 227 secondary metabolites have been isolated from H. sampsonii, including polycyclic polyprenylated acylphloroglucinols (PPAPs), benzophenones, xanthones, flavonoids, naphthodianthrones, anthraquinones and aromatic compounds. These metabolites exhibit various biological activities such as anti-inflammatory, anti-tumor, anti-depressant, anti-oxidant, anti-viral and anti-bacterial effects. PPAPs are considered the main active metabolites with rich biological activities. Despite being known as rich source of PPAPs, the full extent of H. sampsonii biological activities, including their potential as PDE4 inhibitors, remained unclear. Since, previous studies have mainly been based on structural identification of metabolites in H. sampsonii, and efficacy evaluations of these metabolites based on clinical applications of H. sampsonii lack sufficient data. However, current evidence suggest that PPAPs are the most likely material basis for efficacy. From the limited information available so far, there is no evidence of potential safety issues and the safety data are limited. Conclusion: Collectively, this review provides a comprehensive overview of the botany, traditional uses, phytochemistry, pharmacology, and safety of H. sampsonii, a valuable medicinal plant in China with various pharmacological activities. Based on pharmacological studies, H. sampsonii shows potential for treating gastrointestinal and gynecological disorders as well as traumatic injuries, which aligns with traditional medicinal use due to the presence of PPAPs, benzophenones, xanthones, and flavonoids. Therefore, further studies are needed to evaluate the pharmacological effects and elucidate the pharmacological mechanisms. In addition, pharmacological mechanisms and safety evaluation of PPAPs on animal models need to be clarified. Yet, further comprehensive studies are required to elucidate the phytochemical constituents, pharmacological mechanisms, structure-activity relationships, safety evaluation, and quality standards of this plant. Takentogether, this review highlights the potential of H. sampsonii for medical application and drug development.

Based on the Cancer Genome Atlas Database Development of a prognostic model of RNA binding protein in stomach adenocarcinoma.

The purpose of this study was to identify potential RNA binding proteins associated with the survival of gastric adenocarcinoma, as well as the corresponding biological characteristics and signaling pathways of these RNA binding proteins. RNA sequencing and clinical data were obtained from the cancer genome map (N = 32, T = 375) and the comprehensive gene expression database (GSE84437, N = 433). The samples in The Cancer Genome Atlas were randomly divided into a development group and a test group. A total of 1495 RNA binding protein related genes were extracted. Using nonparametric tests to analyze the difference of RNA binding protein related genes, 296 differential RNA binding proteins were obtained, 166 were up-regulated and 130 were down regulated. Twenty prognosis-related RNA binding proteins were screened using Cox regression, including 14 high-risk genes (hazard ratio > 1.0) and 6 low-risk genes (hazard ratio < 1.0). Seven RNA binding protein related genes were screened from the final prognostic model and used to construct a new prognostic model. Using the development group and test group, the model was verified with survival analysis, receiver operating characteristics curves and prognosis analysis curves. A prediction nomogram was finally developed and showed good prediction performance.

Therapeutic potential of Litsea cubeba essential oil in modulating inflammation and the gut microbiome.

Inflammation, a sophisticated and delicately balanced physiological mechanism, is paramount to the host's immunological defense against pathogens. However, unfettered and excessive inflammation can be instrumental in engendering a plethora of chronic ailments and detrimental health repercussions, notably within the gastrointestinal tract. Lipopolysaccharides (LPS) from bacteria are potent endotoxins capable of instigating intestinal inflammation through the disruption of the intestinal epithelial barrier and the stimulation of a pro-inflammatory immune response. In this study, we sought to investigate the influence of Litsea cubeba essential oil (LCEO) on LPS-induced intestinal inflammation and associated changes in the gut microbiota. We investigated the therapeutic potential of LCEO for gut health, with particular emphasis on its gut protective properties, anti-inflammatory properties and modulation of the gut microbiome. LCEO exhibited protective effects on colonic tissue by protecting crypts and maintaining epithelial integrity, and anti-inflammatory properties by reducing TNF-α, IL-6, and IL-1ß levels in the liver and intestine. Citral, a major component of LCEO, showed robust binding to IL-1ß, IL-6, and TNF-α, exerting anti-inflammatory effects through hydrogen bonding interactions. Using community barplot and LEfSe analyses, we detected significant variation in microbial composition, identified discrete biomarkers, and highlighted the influence of essential oils on gut microbial communities. Our research suggests that LCEO may be a promising natural compound for ameliorating diarrhea and intestinal inflammation, with potential implications for modulating the gut microbiome. These observations provide invaluable insight into the potential therapeutic role of LCEO as a natural anti-inflammatory agent for treating intestinal inflammatory disorders, particularly in the setting of a dysregulated immune response and altered gut microbiota. Furthermore, our findings highlight the need to understand the complex interplay between the host, the gut microbiome and natural products in the context of inflammatory diseases.

LC-MS/MS-based metabolomics approach identified novel antioxidant flavonoids associated with drought tolerance in citrus species.

Citrus fruits are cultivated around the world, and they face drought stress frequently during their growth and development. Previous studies showed that citrus plants biosynthesized flavonoid compounds in response to abiotic stress. In this study, we have quantified 37 flavonoid compounds from the leaves of three distinct citrus species including sour orange (drought-tolerant), pummelo 'Majia you pummelo' (drought-sensitive), and lemon (drought-sensitive). The 37 flavonoids consisted of 12 flavones, 10 flavonols, 6 flavanones, 5 isoflavanones, and 1 each for chalcone, flavanol, flavanonol, and flavone glycoside. Drought stress differentially altered the flavonoid metabolism in drought-tolerant and drought-sensitive citrus species. The kaempferol 3-neohesperidoside was 17-fold higher in sour orange (124.41 nmol/L) after 18 days of drought stress than lemon (7.33 nmol/L). In sour orange, neohesperidin (69.49 nmol/L) was 1,407- and 37-fold higher than pummelo and lemon, respectively. In sour orange, some flavonoids were significantly increased, such as vitexin, neohesperidin, cynaroside, hyperoside, genistin, kaempferol 3-neohesperidoside, eriocitrin, and luteolin, in response to drought stress, whereas in lemon, these flavonoids were significantly decreased or not altered significantly in response to drought stress. Moreover, the total contents of flavonoids and antioxidant activity were increased in sour orange as compared with pummelo and lemon. The genes associated with flavonoid biosynthesis (PAL, CHI, FLS, GT1, F3H, F3'M, C4H, 4CL, FLS, FG2, FG3, and CYP81E1) were more highly expressed in sour orange leaves than in pummelo and lemon after drought stress. These outcomes showed that pummelo and lemon failed to biosynthesize antioxidant flavonoids to cope with the prolonged drought stress, whereas the sour orange biosynthesized fortified flavonoid compounds with increased antioxidant activity to detoxify the harmful effects of reactive oxygen species produced during drought stress.

Metagenomic and metabolomic analyses show correlations between intestinal microbiome diversity and microbiome metabolites in ob/ob and ApoE-/- mice.

Obesity and atherosclerosis are the most prevalent metabolic diseases. ApoE-/- and ob/ob mice are widely used as models to study the pathogenesis of these diseases. However, how gut microbes, gut bacteriophages, and metabolites change in these two disease models is unclear. Here, we used wild-type C57BL/6J (Wt) mice as normal controls to analyze the intestinal archaea, bacteria, bacteriophages, and microbial metabolites of ob/ob and ApoE-/- mice through metagenomics and metabolomics. Analysis of the intestinal archaea showed that the abundances of Methanobrevibacter and Halolamina were significantly increased and decreased, respectively, in the ob/ob group compared with those in the Wt and ApoE-/- groups (p < 0.05). Compared with those of the Wt group, the relative abundances of the bacterial genera Enterorhabdus, Alistipes, Bacteroides, Prevotella, Rikenella, Barnesiella, Porphyromonas, Riemerella, and Bifidobacterium were significantly decreased (p < 0.05) in the ob/ob mice, and the relative abundance of Akkermansia was significantly decreased in the ApoE-/- group. The relative abundances of A. muciniphila and L. murinus were significantly decreased and increased, respectively, in the ob/ob and ApoE-/- groups compared with those of the Wt group (p < 0.05). Lactobacillus_ prophage_ Lj965 and Lactobacillus _ prophage _ Lj771 were significantly more abundant in the ob/ob mice than in the Wt mice. Analysis of the aminoacyl-tRNA biosynthesis metabolic pathway revealed that the enriched compounds of phenylalanine, glutamine, glycine, serine, methionine, valine, alanine, lysine, isoleucine, leucine, threonine, tryptophan, and tyrosine were downregulated in the ApoE-/- mice compared with those of the ob/ob mice. Aminoacyl-tRNA synthetases are considered manifestations of metabolic diseases and are closely associated with obesity, atherosclerosis, and type 2 diabetes. These data offer new insight regarding possible causes of these diseases and provide a foundation for studying the regulation of various food nutrients in metabolic disease models.

The formation mechanisms of key flavor substances in stinky tofu brine based on metabolism of aromatic amino acids.

Understanding the formation mechanism of the flavor compounds in stinky tofu brine is crucial for controlling the flavor quality of Changsha stinky tofu. Dynamic changes in associated bacteria, enzymes, and differential metabolites in the metabolic pathway of aromatic amino acids in brine were investigated. Results showed that phenol (0.39～89.96 µg/mL), p-cresol (0.19～389.62 µg/mL), indole (1.14～242.97 µg/mL), 3-methylindole (0.14～3.00 µg/mL) were the key flavor substances of brine. The main associated bacteria Clostridiales bacterium SYSU GA17129, Aneurinibacillus aneurinilyticus, and Anaerosalibacter massiliensis were significantly positively correlated with key flavor substances (P < 0.05). The main associated enzymes were transaminase, decarboxylase, and lyase. In summary, phenol and p-cresol were formed by the metabolism of tyrosine and phenylalanine through five reaction chains, and indole and 3-methylindole were formed by the metabolism of tryptophan through one and three reaction chains, respectively.

Enhanced Antimicrobial Activity of N-Terminal Derivatives of a Novel Brevinin-1 Peptide from The Skin Secretion of Odorrana schmackeri.

Antimicrobial peptides (AMPs) are promising therapeutic alternatives compared to conventional antibiotics for the treatment of drug-resistant bacterial infections. However, the application of the overwhelming majority of AMPs is limited because of the high toxicity and high manufacturing costs. Amphibian skin secretion has been proven to be a promising source for the discovery and development of novel AMPs. Herein, we discovered a novel AMP from the skin secretion of Odorrana schmackeri, and designed the analogues by altering the key factors, including conformation, net charge and amphipathicity, to generate short AMPs with enhanced therapeutic efficacy. All the peptides were chemically synthesised, followed by evaluating their biological activity, stability and cytotoxicity. OSd, OSe and OSf exhibited broad-spectrum antibacterial effects, especially OSf, which presented the highest therapeutic index for the tested bacteria. Moreover, these peptides displayed good stability. The results from scanning electron microscopy and transmission electron microscopy studies, indicated that brevinin-OS, OSd, OSe and OSf possessed rapid bactericidal ability by disturbing membrane permeability and causing the release of cytoplasmic contents. In addition, OSd, OSe and OSf dramatically decreased the mortality of waxworms acutely infected with MRSA. Taken together, these data suggested that a balance between positive charge, degrees of α-helicity and hydrophobicity, is necessary for maintaining antimicrobial activity, and these data successfully contributed to the design of short AMPs with significant bactericidal activity and cell selectivity.

Pharmacological Effects of a Novel Bradykinin-Related Peptide (RR-18) from the Skin Secretion of the Hejiang Frog (Ordorrana hejiangensis) on Smooth Muscle.

Bradykinin (BK) and bradykinin-related peptides (BRPs), which were identified from a diversity of amphibian skin secretions, exerted contractile and relaxing effects on non-vascular and vascular smooth muscle, respectively. Here, we report a novel bradykinin-related peptide with a molecular mass of 1890.2 Da, RVAGPDKPARISGLSPLR, which was isolated and identified from Ordorrana hejiangensis skin secretions, followed by a C-terminal extension sequence VAPQIV. The biosynthetic precursor-encoding cDNA was cloned by the "shotgun" cloning method, and the novel RR-18 was identified and structurally confirmed by high-performance liquid chromatography (HPLC) and tandem mass spectrometry (MS/MS). Subsequently, the myotropic activity of the synthetic replicate of RR-18 was investigated on the rat bladder, uterus, tail artery and ileum smooth muscle. The peptide was named RR-18 in accordance (R = N-terminal arginine, R = C-terminal arginine, 18 = number of residues). In this study, the synthetic replicates of RR-18 showed no agonist/antagonism of BK-induced rat bladder and uterus smooth muscle contraction. However, it displayed an antagonism of bradykinin-induced rat ileum contraction and arterial smooth muscle relaxation. The EC50 values of BK for ileum and artery, were 214.7 nM and 18.3 nM, respectively. When the tissue was pretreated with the novel peptide, RR-18, at the maximally effective concentration of bradykinin (1 × 10-6 M), bradykinin-induced contraction of the ileum and relaxation of the arterial smooth muscle was reduced by 50-60% and 30-40%, respectively. In conclusion, RR-18 represents novel bradykinin antagonising peptide from amphibian skin secretions. It may provide new insight into possible treatment options for chronic pain and chronic inflammation.

Microbial quality and formation of biogenic amines in the meat and edible offal of Camelus dromedaries with a protection trial using gingerol and nisin.

This study aimed firstly at the investigation of the microbial status of the camel meat and edible offal including liver, kidneys, lungs, rumen, and duodenum distributed at local markets of Egypt. Total plate count, total psychrophilic counts, total Enterobacteriaceae count, the most probable number of coliforms, and total mold counts were monitored at the collected samples. The produced biogenic amines (BA) in the camel meat and offal were further estimated. An experimental trial to investigate the antimicrobial potentials of either nisin, gingerol, or an equal mixture of both using camel muscle as a food matrix was conducted. The achieved results declared a high microbial load in the camel meat and the offal. Duodenum and rumen had the highest microbial counts followed by lungs, kidneys, liver, and muscle, respectively. Similarly, duodenum and rumen had the highest levels of BA, including tyramine, spermine, putrescine, cadaverine, and histamine. Both of nisin and ginger showed significant antimicrobial properties in a concentration-dependent manner. Thus, efficient hygienic measures during the handling of camel meat are highly recommended. In addition, using nisin, gingerol, or a mixture of both is an efficient strategy for improving the microbiological quality of the camel meat.

Neuroprotection of Cyperus esculentus L. orientin against cerebral ischemia/reperfusion induced brain injury.

Orientin is a flavonoid monomer. In recent years, its importance as a source of pharmacological active substance is growing rapidly due to its properties such as anti-myocardial ischemia, anti-apoptosis, anti-radiation, anti-tumor, and anti-aging. However, the neuroprotective effects of Orientin on stroke injury have not been comprehensively evaluated. The aim of the present study was thus to investigate the neuroprotective capacity and the potential mechanisms of Cyperus esculentus L. orientin (CLO) from Cyperus esculentus L. leaves against ischemia/reperfusion (I/R) injury using standard orientin as control. For in vitro studies, we treated HT22 cells with CoCl2 as an in vitro ischemic injury model. HT22 cells in the control group were treated with CoCl2. For in vivo studies, we used rat models of middle cerebral artery occlusion, and animals that received sham surgery were used as controls. We found that CLO protected CoCl2-induced HT22 cells against ischemia/reperfusion injury by lowering lipid peroxidation and reactive oxygen species formation as well as decreasing protein oxidation. However, CLO did not reduce the release of lactate dehydrogenase nor increase the activity of superoxide dismutase. Results showed that CLO could decrease neurological deficit score, attenuate brain water content, and reduce cerebral infarct volume, leading to neuroprotection during cerebral ischemia-reperfusion injury. Our studies indicate that CLO flavonoids can be taken as a natural antioxidant and bacteriostastic substance in food and pharmaceutical industry. The molecular mechanisms of CLO could be at least partially attributed to the antioxidant properties and subsequently inhibiting activation of casepase-3. All experimental procedures and protocols were approved on May 16, 2016 by the Experimental Animal Ethics Committee of Xinjiang Medical University of China (approval No. IACUC20160516-57).

Bioevaluation of Ranatuerin-2Pb from the Frog Skin Secretion of Rana pipiens and its Truncated Analogues.

Antimicrobial peptides (AMPs) are considered as a promising agent to overcome the drug-resistance of bacteria. Large numbers of AMPs have been identified from the skin secretion of Rana pipiens, including brevinins, ranatuerins, temporins and esculentins. In this study, the cDNA precursor of a broad-spectrum antimicrobial peptide, ranatuerin-2Pb, was cloned and identified. Additionally, two truncated analogues, RPa and RPb, were synthesised to investigate the structure-activity relationship of ranatuerin-2Pb. RPa lost antimicrobial activity against Candida albicans, MRSA, Enterococcus faecalis and Pseudomonas aeruginosa, while RPb retained its broad-spectrum antimicrobial activity. Additionally, ranatuerin-2Pb, RPa and RPb demonstrated inhibition and eradication effects against Staphylococcusaureus biofilm. RPb showed a rapid bacterial killing manner via membrane permeabilization without damaging the cell membrane of erythrocytes. Moreover, RPb decreased the mortality of S. aureus infected Galleria mellonella larvae. Collectively, our results suggested that RPb may pave a novel way for natural antimicrobial drug design.

Pharmacological Effects of Two Novel Bombesin-Like Peptides from the Skin Secretions of Chinese Piebald Odorous Frog (Odorrana schmackeri) and European Edible Frog (Pelophylax kl. esculentus) on Smooth Muscle.

Bombesin-like peptides, which were identified from a diversity of amphibian skin secretions, have been demonstrated to possess several biological functions such as stimulation of smooth muscle contraction and regulation of food intake. Here, we report two novel bombesin-like peptides, bombesin-OS and bombesin-PE, which were isolated from Odorrana schmackeri and Pelophylax kl. esculentus, respectively. The mature peptides were identified and structurally confirmed by high performance Scliquid chromatography (HPLC) and tandem mass spectrometry (MS/MS). Subsequently, the effects of these purified chemically-synthetic peptides on smooth muscle were determined in bladder, uterus, and ileum. The synthetic replications were revealed to have significant pharmacological effects on these tissues. The EC50 values of bombesin-OS for bladder, uterus and ileum, were 10.8 nM, 33.64 nM, and 12.29 nM, respectively. Furthermore, compared with bombesin-OS, bombesin-PE showed similar contractile activity on ileum smooth muscle and uterus smooth muscle, but had a higher potency on bladder smooth muscle. The EC50 value of bombesin-OS for bladder was around 1000-fold less than that of bombesin-PE. This suggests that bombesin-OS and bombesin-PE have unique binding properties to their receptors. The precursor of bombesin-OS was homologous with that of a bombesin-like peptide, odorranain-BLP-5, and bombesin-PE belongs to the ranatensin subfamily. We identified the structure of bombesin-OS and bombesin-PE, two homologues peptides whose actions may provide a further clue in the classification of ranid frogs, also in the provision of new drugs for human health.