Antibiotic prescribing and bacterial infection in COVID-19 inpatients in Southeast Asia: a systematic review and meta-analysis.

Background: The prescribing of antibiotics to treat COVID-19 patients has been observed to occur frequently, often without clear justification. This trend raises concerns that it may have exacerbated antimicrobial resistance (AMR). Despite longstanding concerns over AMR in Southeast Asian countries, data on this issue are notably lacking. Objectives: To explore the impact of COVID-19 on antibiotic prescribing, bacterial infection prevalence and common resistant pathogens in COVID-19 inpatients. Methods: We searched PubMed, EMBASE, Web of Science and ThaiJO (a Thai academic database) to identify studies conducted in ASEAN member countries and published between December 2019 and March 2023. Screening and data extraction were done by two independent reviewers, with results synthesized using random-effects meta-analyses and descriptive statistical analyses. This review was registered with PROSPERO (CRD42023454337). Results: Of the 29 studies (19 750 confirmed COVID-19 cases) included for final analysis, the antibiotic prescribing rate was 62.0% (95%CI: 46.0%-76.0%) with a prescribing rate of 58.0% (21.0%-91.0%) in mild/moderate cases versus 91.0% (82.0%-98.0%) in severe/critical cases. Notably, 80.5% of antibiotics prescribed fall under the WHO AWaRe 'Watch' list, followed by 'Access' at 18.4% and 'Reserve' at 1.0%. The reported bacterial infection prevalence was 16.0% (7.0%-29.0%), with Acinetobacter baumannii being the most common resistant bacterium at 7.7%. Singapore was notable for its lower antibiotic prescribing rate of 17.0% and a lower bacterial infection rate of 10.0%. Conclusions: High antibiotic prescribing rates, disproportionate to bacterial infections and varying practices for COVID-19 inpatients across countries highlight the urgent need for this region to collaborate to tackle and mitigate AMR.

Impact of low-level exposure to antibiotics on bile acid homeostasis in adults: Implication for human safety thresholds.

Bile acid homeostasis is critical to human health. Low-level exposure to antibiotics has been suggested to potentially disrupt bile acid homeostasis by affecting gut microbiota, but relevant data are still lacking in humans, especially for the level below human safety threshold. We conducted a cross-sectional study in 4247 Chinese adults by measuring 34 parent antibiotics and their metabolites from six common categories (i.e., tetracyclines, qinolones, macrolides, sulfonamides, phenicols, and lincosamides) and ten representative bile acids in fasting morning urine using liquid chromatography coupled to mass spectrometry. Daily exposure dose of antibiotics was estimated from urinary concentrations of parent antibiotics and their metabolites. Urinary bile acids and their ratios were used to reflect bile acid homeostasis. The estimated daily exposure doses (EDED) of five antibiotic categories with a high detection frequency (i.e., tetracyclines, qinolones, macrolides, sulfonamides, and phenicols) were significantly associated with urinary concentrations of bile acids and decreased bile acid ratios in all adults and the subset of 3898 adults with a cumulative ratio of antibiotic EDED to human safety threshold of less than one. Compared to a negative detection of antibiotics, the lowest EDED quartiles of five antibiotic categories and four individual antibiotics with a high detection frequency (i.e., ciprofloxacin, ofloxacin, trimethoprim, and florfenicol) in the adults with a positive detection of antibiotics had a decrease of bile acid ratio between 6.6% and 76.6%. Except for macrolides (1.2×102 ng/kg/day), the medians of the lowest EDED quartile of antibiotic categories and individual antibiotics ranged from 0.32 ng/kg/day to 10 ng/kg/day, which were well below human safety thresholds. These results suggested that low-level antibiotic exposure could disrupt bile acid homeostasis in adults and existing human safety thresholds may be inadequate in safeguarding against the potential adverse health effects of low-level exposure to antibiotics.

Prevalence of antibiotic prescribing in COVID-19 patients in China and other low- and middle-income countries during the pandemic (December 2019-March 2021): a systematic review and meta-analysis.

OBJECTIVES: Low- and middle-income countries (LMICs) are particularly vulnerable to the threat of antimicrobial resistance (AMR). Use of antibiotics to treat COVID-19 patients during the pandemic may have contributed to increasing the AMR burden, but systematic evidence is lacking. METHODS: We searched Web of Science, EMBASE, PubMed, China National Knowledge Infrastructure (CNKI) and VIP databases from 1 December 2019 to 31 March 2021. Interventional and observation studies across all settings that reported antibiotic use in at least 10 COVID-19 patients were included. We restricted publications to English and Chinese languages. Screening and data extraction were undertaken by at least two independent reviewers. Results were synthesized using random-effects meta-analyses. Subgroup analyses and meta-regression were used to explore heterogeneities. This review was registered with PROSPERO (CRD42021288291). RESULTS: We included 284 studies involving 210 611 participants in 19 countries. The antibiotic prescribing rates (APRs) in COVID-19 inpatients were 71.7% (95% CI 66.7%-76.5%) in China and 86.5% (77.1%-93.9%) in other LMICs, respectively. APR was lower in mild/moderate cases in China [66.9% (57.9%-75.4%) compared with 91.8% (71.4%-100%) in other LMICs]. High APRs were found among pregnant women and the elderly in China. Disparities in APRs of other patient groups were identified. In studies reporting bacterial infections, the prevalence was 17.3% (10.0%-25.9%) in China and 24.9% (0.1%-68.8%) in other LMICs. Several antibiotics on the WHO 'Watch' and 'Reserve' lists were prescribed frequently in LMICs. CONCLUSIONS: Inappropriate antibiotic use and high prevalence of antibiotic prescribing were found in COVID-19 inpatients in many LMICs.

Assessment of community-wide antimicrobials usage in Eastern China using wastewater-based epidemiology.

Wastewater-based epidemiology (WBE) has potential to identify the epidemiological links between people, animals, and the environment, as part of antimicrobial resistance (AMR) surveillance. In this study, we investigated six wastewater treatment plants (WWTPs) serving six communities located in two regions in Eastern China: Site A in Zhejiang and site B in Jiangsu province to assess the public use of antimicrobial agents (AA). Fifty antimicrobials and 24 of their metabolites were quantified using ultraperformance liquid chromatography coupled with triple quadrupole tandem mass spectrometry (UPLC-MS/MS). Spatiotemporal trends were established for measured concentrations, daily loads, and population-normalised daily loads. Daily AA mass loads varied between 1.6 g/day and 324.6 g/day reflecting the WWTP scales, with macrolides and ß-lactams showing the highest overall environmental burden at 223.7 g/day and 173.7 g/day, respectively. Emissions of antibiotic residues from manufacturing have been observed, with the peak daily load 12-fold higher than the overall load from a community serving a population of over 600,000. Community exposure levels of 225.2 ± 156.2 mg/day/1000 inhabitant and 351.9 ± 133.5 mg/day/1000 inhabitant were recorded in site A and B, respectively. Paired parent-metabolites analysis identified a large proportion (64-78%) of un-metabolised metronidazole and clindamycin at site B, indicating improper disposal of unused drugs either in the community or in livestock production. Consumption levels, calculated via WBE, suggested relatively low antimicrobial usage in Eastern China compared to other areas in China. This first application of WBE in Eastern China to assess the community-wide exposure to AAs has potential to inform regional antimicrobial stewardship.

Antibiotic Use and Bacterial Infection in COVID-19 Patients in the Second Phase of the SARS-CoV-2 Pandemic: A Scoping Review.

This scoping review aimed to explore the prevalence and patterns of global antibiotic use and bacterial infection in COVID-19 patients from studies published between June 2020 and March 2021. This review was reported in line with the Preferred Reporting of Systematic Reviews and Meta-Analyses (PRISMA) extension for Scoping Reviews, and the protocol is registered with the Open Science Framework. Compared with our previously-published review of the period (December 2019-June 2020), the antibiotic prescribing rate for COVID-19 patients (June 2020-March 2021) was found to have declined overall (82.3% vs. 39.7%), for mild and moderate patients (75.1% vs. 15.5%), and for severe and critical patients (75.3% vs. 48.3%). The seven most frequently prescribed antibiotics in COVID-19 patients were all on the "Watch" list of the WHO AWaRe antibiotics classification. The overall reported bacterial infection rate in COVID-19 patients was 10.5%, and the most frequently reported resistant pathogen in COVID-19 patients was Staphylococcus aureus, followed by Pseudomonas aeruginosa, Escherichia coli, and Klebsiella pneumoniae. There is an urgent need to establish comprehensive and consistent guidelines to assist clinicians in selecting appropriate antibiotics for COVID-19 patients when needed. The resistance data on the most frequently used antibiotics for COVID-19 patients for certain resistant pathogens should be closely monitored.

Impacts of Antibiotic Residues in the Environment on Bacterial Resistance and Human Health in Eastern China: An Interdisciplinary Mixed-Methods Study Protocol.

Antibiotic resistance is a global health challenge that threatens human and animal lives, especially among low-income and vulnerable populations in less-developed countries. Its multi-factorial nature requires integrated studies on antibiotics and resistant bacteria in humans, animals, and the environment. To achieve a comprehensive understanding of the situation and management of antibiotic use and environmental transmission, this paper describes a study protocol to document human exposure to antibiotics from major direct and indirect sources, and its potential health outcomes. Our mixed-methods approach addresses both microbiological and pathogen genomics, and epidemiological, geospatial, anthropological, and sociological aspects. Implemented in two rural residential areas in two provinces in Eastern China, linked sub-studies assess antibiotic exposure in population cohorts through household surveys, medicine diaries, and biological sampling; identify the types and frequencies of antibiotic resistance genes in humans and food-stock animals; quantify the presence of antibiotic residues and antibiotic resistance genes in the aquatic environment, including wastewater; investigate the drivers and behaviours associated with human and livestock antibiotic use; and analyse the national and local policy context, to propose strategies and systematic measurements for optimising and monitoring antibiotic use. As a multidisciplinary collaboration between institutions in the UK and China, this study will provide an in-depth understanding of the influencing factors and allow comprehensive awareness of the complexity of AMR and antibiotic use in rural Eastern China.

Cluster randomised controlled trial to assess a tailored intervention to reduce antibiotic prescribing in rural China: study protocol.

INTRODUCTION: Up to 80% of patients with respiratory tract infections (RTI) attending healthcare facilities in rural areas of China are prescribed antibiotics, many of which are unnecessary. Since 2009, China has implemented several policies to try to reduce inappropriate antibiotic use; however, antibiotic prescribing remains high in rural health facilities. METHODS AND ANALYSIS: A cluster randomised controlled trial will be carried out to estimate the effectiveness and cost effectiveness of a complex intervention in reducing antibiotic prescribing at township health centres in Anhui Province, China. 40 Township health centres will be randomised at a 1:1 ratio to the intervention or usual care arms. In the intervention group, practitioners will receive an intervention comprising: (1) training to support appropriate antibiotic prescribing for RTI, (2) a computer-based treatment decision support system, (3) virtual peer support, (4) a leaflet for patients and (5) a letter of commitment to optimise antibiotic use to display in their clinic. The primary outcome is the percentage of antibiotics (intravenous and oral) prescribed for RTI patients. Secondary outcomes include patient symptom severity and duration, recovery status, satisfaction, antibiotic consumption. A full economic evaluation will be conducted within the trial period. Costs and savings for both clinics and patients will be considered and quality of life will be measured by EuroQoL (EQ-5D-5L). A qualitative process evaluation will explore practitioner and patient views and experiences of trial processes, intervention fidelity and acceptability, and barriers and facilitators to implementation. ETHICS AND DISSEMINATION: Ethical approval was obtained from the Biomedical Research Ethics Committee of Anhui Medical University (Ref: 20180259); the study has undergone due diligence checks and is registered at the University of Bristol (Ref: 2020-3137). Research findings will be disseminated to stakeholders through conferences and peer-reviewed journals in China, the UK and internationally. TRIAL REGISTRATION NUMBER: ISRCTN30652037.

RBD-homodimer, a COVID-19 subunit vaccine candidate, elicits immunogenicity and protection in rodents and nonhuman primates.

The pandemic of COVID-19 caused by SARS-CoV-2 has raised a new challenges to the scientific and industrious fields after over 1-year spread across different countries. The ultimate approach to end the pandemic is the timely application of vaccines to achieve herd immunity. Here, a novel SARS-CoV-2 receptor-binding domain (RBD) homodimer was developed as a SARS-CoV-2 vaccine candidate. Formulated with aluminum adjuvant, RBD dimer elicited strong immune response in both rodents and non-human primates, and protected mice from SARS-CoV-2 challenge with significantly reducing viral load and alleviating pathological injury in the lung. In the non-human primates, the vaccine could prevent majority of the animals from SARS-CoV-2 infection in the respiratory tract and reduce lung damage. In addition, antibodies elicited by this vaccine candidate showed cross-neutralization activities to SARS-CoV-2 variants. Furthermore, with our expression system, we provided a high-yield RBD homodimer vaccine without additional biosafety or special transport device supports. Thus, it may serve as a safe, effective, and low-cost SARS-CoV-2 vaccine candidate.

Antimicrobial Use in COVID-19 Patients in the First Phase of the SARS-CoV-2 Pandemic: A Scoping Review.

This scoping review provides new evidence on the prevalence and patterns of global antimicrobial use in the treatment of COVID-19 patients; identifies the most commonly used antibiotics and clinical scenarios associated with antibiotic prescribing in the first phase of the pandemic; and explores the impact of documented antibiotic prescribing on treatment outcomes in COVID-19 patients. The review complies with PRISMA guidelines for Scoping Reviews and the protocol is registered with the Open Science Framework. In the first six months of the pandemic, there was a similar mean antibiotic prescribing rate between patients with severe or critical illness (75.4%) and patients with mild or moderate illness (75.1%). The proportion of patients prescribed antibiotics without clinical justification was 51.5% vs. 41.9% for patients with mild or moderate illness and those with severe or critical illness. Comparison of patients who were provided antibiotics with a clinical justification with those who were given antibiotics without clinical justification showed lower mortality rates (9.5% vs. 13.1%), higher discharge rates (80.9% vs. 69.3%), and shorter length of hospital stay (9.3 days vs. 12.2 days). In the first 6 months of the pandemic, antibiotics were prescribed for COVID-19 patients regardless of severity of illness. A large proportion of antibiotic prescribing for mild and moderate COVID-19 patients did not have clinical evidence of a bacterial co-infection. Antibiotics may not be beneficial to COVID-19 patients without clinical evidence of a bacterial co-infection.

Identification of fukinolic acid from Cimicifuga heracleifolia and its derivatives as novel antiviral compounds against enterovirus A71 infection.

Human enterovirus 71 (EV-A71) infections cause a wide array of diseases ranging from diarrhoea and rashes to hand-foot-and-mouth disease and, in rare cases, severe neurological disorders. No specific antiviral drug therapy is currently available. Extracts from 75 Chinese medicinal plants selected for antiviral activity based on the Chinese pharmacopeia and advice from traditional Chinese medicine clinicians were tested for activity against EV-A71. The aqueous extract of the rhizome of Cimicifuga heracleifolia (Sheng Ma) and Arnebia euchroma (Zi Cao) showed potent antiviral activity. The active fractions were isolated by bioassay-guided purification, and identified by a combination of high-resolution mass spectrometry and nuclear magnetic resonance. Fukinolic acid and cimicifugic acid A and J, were identified as active anti-EV-A71 compounds for C. heracleifolia, whereas for A. euchroma, two caffeic acid derivatives were tentatively deduced. Commercially available fukinolic acid analogues such as L-chicoric acid and D-chicoric also showed in vitro micromolar activity against EV-A71 lab-strain and clinical isolates.

[Electroacupuncture Improves Pulmonary Function of Rats with Chronic Obstructive Pulmonary Disease by Down-regulating Inflammatory Reaction and Expression of Macrophage Migration Inhibitory Factor/CD 74-CD 44/p 38 MAPK Signaling in Lung Tissues].

OBJECTIVE: To observe the effect of electroacupuncture (EA) at "Zusanli" (ST 36) and "Feishu" (BL 13) on pulmonary function, inflammatory reaction and expression of macrophage migration inhibitory factor (MIF) and its receptor complex CD 74-CD 44, etc. in rats with chronic obstructive pulmonary disease (COPD), so as to explore its mechanism underlying improvement of COPD. METHODS: Thirty male SD rats were randomly divided into normal, model and EA groups (n＝10 in each group). The COPD model was established by intratracheal infusion of Lipopolysaccharide (LPS, 1 mg/mL) and forced smoke-inhaling. EA was applied to bilateral ST 36 and BL 13 for 30 min, once daily for 7 days. The rat's lung function (forced vital capacity [FVC], forced expiratory capacity ratio ([FEV 0.1/FVC] and [FEV 0.3/FVC]) was detected under anesthesia. Pathological changes of the lung tissue were detected by H．E. staining, and the contents of MIF, tumor necrosis factor-α (TNF-α), interleukin-1 ß (IL-1 ß) and IL-8 in serum, bronchoalveolar lavage fluid (BALF) and lung tissue were assayed by ELISA. The immunoactivity of CD 74 and CD 44 was detected by immunohistochemistry, and the expression levels of MIF, CD 74, CD 44 and p 38 MAPK mRNAs and proteins were examined by quantitative RT-PCR and Western blot, respectively. RESULTS: Compared with the normal group, the FVC, FEV 0.1, FEV 0.3, FEV 0.1/FVC and FEV 0.3/FVC levels were significantly decreased in the model group (P<0.01). After EA treatment, the FVC, FEV 0.1, FEV 0.3, FEV 0.1/FVC and FEV 0.3/FVC were significantly increased (P<0.01, P<0.05), suggesting an improvement of the pulmonary function after EA. H．E. staining showed that the severity of modeling induced alveolar expansion and inflammatory cell infiltration in the lung tissue was relatively milder in the EA group relevant to the model group. The contents of MIF, TNF-α， IL-1 ß and IL-8 in the serum, BALF and lung tissues were significantly higher in the model group than in the normal group (P<0.01), and significantly down-regulated in the EA group relevant to the model group (P<0.01). The expression levels of MIF, CD 74, CD 44 and p 38 MAPK mRNAs and proteins and the immunoactivity levels of CD 74, CD 44 in the lung tissue were obviously higher in the model group than those in the normal group (P<0.01), and considerably lower in the EA group than those in the model group (P<0.01). There was a positive correlation between p 38 MAPK and MIF in mRNA and protein expression levels (P<0.01). CONCLUSION: EA intervention can improve the pulmonary function in COPD rats, which may be related to its effects in inhibiting inflammatory reaction, and MIF/CD 74-CD 44/p 38 MAPK signaling pathway.

Electro-acupuncture regulates the cholinergic anti-inflammatory pathway in a rat model of chronic obstructive pulmonary disease.

OBJECTIVE: Acupuncture has a definite therapeutic effect on chronic obstructive pulmonary disease (COPD), and the cholinergic anti-inflammatory pathway (CAP) has been shown to be involved in regulation of inflammation. In this study, we investigated whether electro-acupuncture (EA) affects the CAP in COPD. METHODS: Sprague-Dawley rats were induced into COPD through exposure to cigarette smoke combined with lipopolysaccharide. EA treatment was applied at Zusanli (ST36) and Feishu (BL13) points for 30 min/d for 7 d. Seventy-two rats were randomly divided into six study groups, including normal, normal + EA, normal + α-bungarotoxin (α-BGT) (the antagonist of the nicotinic acetylcholine receptor α7 subunit (α7nAChR)) + EA, COPD, COPD + EA, and COPD + α-BGT + EA. Lung function, pathology and vagus nerve discharge were tested. The levels of acetylcholine (ACh), acetylcholinesterase (AChE), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in bronchoalveolar lavage fluid (BALF) and lung tissue were measured by enzyme-linked immunosorbent assay. The mRNA and protein expression and immunoreactivity of α7nAChR and its postreceptor inflammation signal pathway, including janus kinase 2 (JAK2), signal transducers and activators of transcription 3 (STAT3), nuclear factor-κB (NF-κB), were observed by quantitative reverse transcription-polymerase chain reaction, Western blot and immunohistochemistry. RESULTS: Compared with normal rats, there were a significant decline in lung function and discharge of the vagus nerve (P < 0.01), a marked sign of lung inflammation and an increase of ACh, AChE, IL-6 and TNF-α level in BALF or lung tissue (P < 0.05, P < 0.01) and higher expression of α7nAChR, JAK2, STAT3 and NF-κB (P < 0.05, P < 0.01) in the COPD rats. In rats receiving EA, the lung function and vagal discharge were enhanced (P < 0.01), lung inflammation was improved and the levels of ACh, AChE, IL-6 and TNF-α were decreased (P < 0.01). Further, the expression of α7nAChR, JAK2, STAT3 and NF-κB was downregulated (P < 0.05, P < 0.01). However, the above effects of EA were blocked in rats injected with α-BGT (P < 0.01). CONCLUSION: EA treatment can reduce the lung inflammatory response and improve lung function in COPD, which may be related to its involvement in the regulation of CAP.

Monoclonal antibodies directed against VP7 protein of human group B rotavirus.

The aim of this study was to prepare and identify a monoclonal antibody that binds the viral proteins 7 (VP7 protein) of human group B rotavirus (GBRV) and to describe its immunologic characterization. Human group B rotavirus vp7 gene was successfully ligated into pGEX-KG vector and transformed into Escherichia coli TOP10 cells. The glutathione S-transferases (GST)-fusion protein GST-VP7 was induced by Isopropyl ß-D-1-thiogalactopyranoside (IPTG) and immediately purified to immunize BALB/c mice. Splenocytes were then prepared from the immunized mouse and fused with SP2/0 myeloma cell line. In the end we obtained one positive hybridoma cell line stably secreting monoclonal antibody against GST-VP7 protein by indirect enzyme-linked immunosorbent assay (ELISA) and limiting dilution. The production of the monoclonal antibody against GBRV will benefit the further study of GBRV's structures and functions and also lay a solid foundation for the research of disease prevention, clinical diagnosis, and treatment.

Solid dispersion tablets of breviscapine with polyvinylpyrrolidone K30 for improved dissolution and bioavailability to commercial breviscapine tablets in beagle dogs.

Breviscapine, one of cardiovascular drugs extracted from a Chinese herb Erigeron breviscapinus, has been frequently used to treat cardiovascular diseases such as hypertension, angina pectoris, coronary heart disease and stroke. However, its poor water solubility and low bioavailability in vivo severely restrict the clinical application. To overcome these drawbacks, breviscapine solid dispersion tablets consisting of breviscapine, polyvinylpyrrolidone K30 (PVP K30), microcrystalline cellulose and crospovidone were appropriately prepared. In vitro dissolution profiles showed that breviscapine released percentage of solid dispersion tablets reached 90 %, whereas it was only 40 % for commercial breviscapine tablets. Comparative pharmacokinetic study between solid dispersion tablets and commercial products was investigated on the normal beagle dogs after oral administration. Results showed that the bioavailability of breviscapine was greatly increased by 3.45-fold for solid dispersion tablets. The greatly improved dissolution rate and bioavailability might be attributed to intermolecular hydrogen bonding reactions between PVP K30 and scutellarin. These findings suggest that our solid dispersion tablets can greatly improve the bioavailability as well as the dissolution rate of breviscapine.

Fecal metabonomic study of a polysaccharide, MDG-1 from Ophiopogon japonicus on diabetic mice based on gas chromatography/time-of-flight mass spectrometry (GC TOF/MS).

Type 2 Diabetes Mellitus (T2DM) is a chronic metabolic disorder with systemic complications and has been a worldwide epidemic. Ophiopogon japonicus is a traditional Chinese medicine used to treat diabetes for thousands of years. From our previous work, we know that MDG-1, a water-soluble ß-D-fructan polysaccharide from O. japonicas could treat T2DM experimentally. However, MDG-1 is poorly absorbed and its mechanism of action is still unknown. Therefore, a GC TOF/MS-based metabonomic approach in combination with multivariate statistical analysis was performed to investigate the mechanism of MDG-1 in a spontaneous diabetic model. Female diabetic KKay mice (21 weeks old) were randomly divided into a diabetic group (n = 6, gavaged with distilled water) and a MDG-1-Diabetic group (n = 7, gavaged with MDG-1, 300 mg kg(-1)) and female C57BL/6 mice (21 weeks old) were set as controls (n = 6, gavaged with distilled water). After 8-weeks of treatment, feces samples were collected for GC-TOF/MS analysis. Consequently, 12 potential biomarkers were identified, including monosugars (D-tagatose, D-lyxose, D-erythrose, xylo-hexos-5-ulose, 2-deoxy-galactose), butanedioic acid, amino acids (phenylalanine, L-lysine, L-methionine, L-aspartic acid) and purine derivatives (7H-purine, 2'-deoxyinosine). We assume the monosugars and butanedioic acid were the fermentation products of MDG-1 by intestinal microbes and MDG-1 actions against diabetes might be accomplished through the absorbable monosugars and butanedioic acid via suppressing intestinal glucose absorption, enhancing liver glycogenesis, inhibiting glycogenolysis and promoting GLP-1 secretion. Besides, MDG-1 might alleviate diabetes and diabetic nephropathy by reducing 7H-purine and 2'-deoxyinosine. Further omics-driven studies including genomics, proteomics and metabonomics were considered to be carried out to provide direct evidence of gut microbiome contribution to MDG-1 actions.

Synergistic Effect and Mechanism of Cineole and Terpineol on In-vitro Transdermal Delivery of Huperzine A from Microemulsions.

The aim of the present study was to investigate the influence and the mechanisms of cineole and terpineol on the in-vitro transdermal delivery of huperzine A from microemulsions, and their potential synergistic effect on the permeation enhancement. The transdermal delivery of huperzine A from microemulsions with different concentrations of cineole and terpineol through the rat abdominal skin was determined by Franz-type diffusion cells. The partition coefficient of huperzine A between the full thickness skin and microemulsion was determined. Attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) was carried out to analyze the effects of cineole and terpineol on the biophysical properties of the stratum corneum (SC) and the mechanisms of permeation enhancement. These results indicated that cineole and terpineol could synergistically increase the transdermal delivery of huperzine A from microemulsions through increasing the partition and diffusion coefficients of huperzine A. ATR-FTIR studies further validated the synergistic effect and revealed that the enhancing mechanisms were due to increasing the disorderliness and fluidity of SC lipid alkyl chains, disrupting the structure of keratin in SC, and extracting SC lipids. In conclusion, cineole and terpineol, acting synergistically to enhance the transdermal delivery of huperzine A from microemulsions, might provide an alternative permeation enhancer combination for the transdermal delivery of huperzine A.

Effect of metformin on the urinary metabolites of diet-induced-obese mice studied by ultra performance liquid chromatography coupled to time-of-flight mass spectrometry (UPLC-TOF/MS).

Obesity is becoming a health concern worldwide and metformin, a first line anti-diabetic drug, was associated with weight loss under different backgrounds. However, most researches focused on the anti-diabetic mechanism and less attention has been paid on the mechanism of weight loss of metformin. Therefore, we established a metabonomic method to evaluate metformin action in preventing obesity in a high fat diet-induced-obesity (DIO) mice model. 36 male C57BL/6 mice (8-week old) were randomly divided into control group (n=12, normal chow), model group (n=12, high fat chow) and metformin group (n=12, high fat chow and dosed with metformin) over 16 weeks. A urinary metabonomic study using UPLC-TOF/MS was performed in combination with multivariate statistical analysis. In addition, indices of body weight and food intake as well as fasting blood glucose, fed blood glucose, oral glucose tolerance test (OGTT) and plasma insulin were collected. Significant weight loss in metformin-treated mice was achieved and 21 potential biomarkers were identified. Decreased glucose, myristic acid, stearidonic acid, lysoPC (16:0), lysoPC (18:0), L-glutamic acid, L-methionine, L-threonine, L-phenylalanine, L-histidine, L-carnitine, L-malic acid and pantothenic acid in urine indicated that metformin may have exerted effects on energy metabolism. Further, based on the biomarkers, we cautiously propose that tricarboxylic acid cycle (TCA) may have been compromised by metformin and might contribute to the activation of adenosine monophosphate kinase (AMPK), then AMPK activation led to more ß-oxidation of certain fatty acids and augmented lipolysis and thus induced weight loss. Related cellular and molecular studies are being considered to further investigate the underlying mechanism.

Metabolite discovery of helicidum in rat urine with XCMS based on the data of ultra performance liquid chromatography coupled to time-of-flight mass spectrometry.

The present study demonstrates the use of XCMS (various forms (X) of chromatography coupled to mass spectrometry), an open-source software tool primarily used in bioinformatics, on the data of ultra-performance liquid chromatography connected online with a mass spectrometer (UPLC/MS) for the discovery of the metabolites of helicidum in urine after oral single dosage to rats. Helicidum (formaldehydephenyl-O-ß-D-pyranosyl alloside) is the major active component of the fruits of Helicid hilagirica Beed. In China, it is often used in the clinic to treat neurasthenic syndromes, vascular headache, and trigeminal neuralgia with high efficacy and low side effect and toxicity. The urine samples of five rats were collected during 0-4, 4-8, 8-12, 12-16, 16-20, 20-24, 24-32, 32-40, and 40-48 h, respectively, after oral administration of helicidum at a dosage of 25.0 mg/kg. A UPLC coupled to time-of-flight MS (UPLC/TOF MS) was used to analyze the samples. Concerning XCMS, the ".raw" format files were preliminarily converted to the open mzXML format using massWolf-4.3.1 (http://sourceforge.net/projects/sashimi/files/massWolf%20(MassLynx%20converter)/). For converting lots of files a time, we wrote a tool rawTomzXML which also uses massWolf-4.3.1. The data were processed using XCMS version l.26.0 (http://www.bioconductor.org/packages/2.8/bioc/html/xcms.html) running under R version 2.13 (http://http://www.r-project.org/) which provided the running platform for XCMS. The "centWave" method from XCMS was used for chromatographic peak detection. Based on the m/z data of the metabolites obtained by XCMS, MS was used to identify the molecular formula. Nine metabolites were finally found and identified. For six of them, the bio-transformation mechanisms of the parent compound was elucidated: glucuronide conjugation (C(19)H(24)O(14)), reduction (C(13)H(18)O(7)), oxidation (C(13)H(16)O(8)), methylation (C(14)H(18)O(7)), and the mixed transformation of reduction, methylation, and acetylation (C(16)H(22)O(8)). For the other three metabolites, C(11)H(19)N(3)O(9), C(11)H(21)N(3)O(9), and C(14)H(15)NO(7), the bio-transformation mechanisms remain unknown and need further investigation. Calculated as mass of helicidum, the cumulative urine excretion rate of the metabolites was 8.39%. The amount of oxidized helicidum was more than 50% among the metabolites while the parent compound helicidum was 13.28% and the reduced helicidum 11.72%, indicating that oxidation was the major bio-transformation that occurred in vivo.

Characterization using LC/MS of the absorption compounds and metabolites in rat plasma after oral administration of a single or mixed decoction of Shaoyao and Gancao.

Shaoyao-Gancao decoction (SGD), a traditional Chinese formulation containing Paeoniae Radix (SY) and Glycyrrhizae Radix (GC), is commonly used to relieve abdominal pain. However, the absorption and metabolites of the characteristic constituents of the two herbs in vivo have been reported rarely. The purpose of this study was to investigate the compatibility rationality and the mechanism of the enhanced efficiency of SGD. A single or a mixed decoction (SG and S+G, respectively) was orally administered to rats. Blood samples were collected at different intervals following treatment and analyzed by liquid LC/MS. A total of fifteen ingredients (denoted as M1 to M15) were found in both rat plasma after treatment with the two decoctions. Furthermore, the proposed structures of the remained twelve ingredients were obtained except M9, M10 and M15. The quality of the ingredients in the rat plasma showed no significant difference between the two decoctions. However, the quantity of twelve ingredients differed greatly, indicating that the absorption of SG was greater than that of S+G except M7, M12 and M15. As the compositions associated with the efficacy of SG and S+G were inconsistent, the degree of the absorption of the 15 ingredients by the gastrointestinal tract were different, which caused a significantly enhanced efficacy of certain ingredients. This study presents an exploration of the mechanism behind the improved efficacy of individual components in traditional Chinese medicine therapies through combination with other components.

Metabonomic study on the cumulative cardiotoxicity of a pirarubicin liposome powder.

Pirarubicin (THP) is an anthracycline frequently used in the chemotherapy against acute leukemia, malignant lymphoma and several solid tumors. However, its clinical use is severely limited by the development of a progressive dose-dependent cardiomyopathy that results in irreversible congestive heart failure. To provide a strategy for constraining or minimizing the cumulative cardiotoxicity of THP, a pirarubicin liposome powder (L-THP) was appropriately prepared, and the cumulative cardiotoxicity of L-THP and free THP (F-THP) were investigated on Sprague-Dawley rats after 3 successive doses. Urinary samples for metabonomic study, serum samples for biochemical assay, and heart samples for histopathology test were collected. As a result, the metabonomics-based findings such as PLS-DA plotting showed minimal metabolic alterations in L-THP as compared to F-THP, and correlated with the changes of serum biochemical assay and cardiac histopathology as measurements of damage to heart tissue. Our results confirm that when encapsulated into liposomes, the cumulative cardiotoxicity of THP can be greatly ameliorated. Lipophilic aglycone metabolites of THP associated with redox cycling are cardiotoxic for the possibility of reactive oxygen species (ROS) formation. Also, metabonomic analysis shows that the successive doses of THP will lead to severe metabolic pathways disturbances in the cell energy production. Further, the preliminary efficacy study of L-THP on lung cancer was evaluated in the approach of in vitro cytotoxicity on A549 cells by high content screening (HCS) analysis, and L-THP was found to exhibit better therapeutic index against lung cancer than THP.