Diet, lifestyle and gut microbiota composition among Malaysian women with gestational diabetes mellitus: a prospective cohort study

The study addressed a significant gap in the profiling and understanding of the gut microbiota's influence on Malaysian Malay women with gestational diabetes mellitus (GDM). This prospective cohort study aimed to explore the intricate relationship between gut microbiota, dietary choices, and lifestyle factors among Malay women, both with and without GDM. The research specifically focused on participants during the second (T0) and third (T1) trimesters of pregnancy in Johor Bahru, Malaysia. In Part 1 of the study, a diverse pool of pregnant women at T0 was categorized into two groups: those diagnosed with GDM and those without GDM, with a total sample size of 105 individuals. The assessments encompassed demographic, clinical, lifestyle, and dietary factors at the T0 and T1 trimesters. Part 2 of the study delved into microbiome analysis, targeting a better understanding of the gut microbiota among the participants. Stool samples were randomly collected from 50% of the individuals in each group (GDM and non-GDM) at T0 and T1. The collected samples underwent processing, and 16s rRNA metagenomic analysis was employed to study the microbial composition. The results suggested an association between elevated body weight and glucose levels, poor sleep quality, lack of physical activity, greater intake of iron and meat, and reduced fruit consumption among women with GDM compared to non-GDM groups. The microbiome analysis revealed changes in microbial composition over time, with reduced diversity observed in the GDM group during the third trimester. The genera Lactiplantibacillus, Parvibacter, Prevotellaceae UCG001, and Vagococcus positively correlated with physical activity levels in GDM women in the second trimester. Similarly, the genus Victivallis exhibited a strong positive correlation with gravida and parity. On the contrary, the genus Bacteroides and Roseburia showed a negative correlation with omega-3 polyunsaturated fatty acids (PUFAs) in women without GDM in the third trimester. The study highlighted the multifaceted nature of GDM, involving a combination of lifestyle factors, dietary choices, and changes in gut microbiota composition. The findings emphasized the importance of considering these interconnected elements in understanding and managing gestational diabetes among Malaysian Malay women. Further exploration is essential to comprehend the mechanisms underlying this relationship and develop targeted interventions for effective GDM management.

The design of the Deaf in Touch Everywhere (DITE)TM mobile application with Deaf and interpreter communities in Malaysia

Background

Ineffective communication with Deaf individuals in healthcare settings has led to poor outcomes including miscommunication, waste, and errors. To help address these challenges, we developed a mobile app, Deaf in Touch Everywhere (DITETM) which aims to connect the Deaf community in Malaysia with a pool of off-site interpreters through secure video conferencing.

Objectives

The aims of this study were to (a) assess the feasibility and acceptability of measuring unified theory of acceptance and use of technology (UTAUT) constructs for DITETM with the Deaf community and Malaysian sign language (BIM) interpreters and (b) seek input from Deaf people and BIM interpreters on DITETM to improve its design.

Methods

Two versions of the UTAUT questionnaire were adapted for BIM interpreters and the Deaf community. Participants were recruited from both groups and asked to test the DITE app features over a 2-week period. They then completed the questionnaire and participated in focus group discussions to share their feedback on the app.

Results

A total of 18 participants completed the questionnaire and participated in the focus group discussions. Ratings of performance expectancy, effort expectancy, facilitating conditions and behavioural intention were high across both groups, and suggestions were provided to improve the app. High levels of engagement suggest that measurement of UTAUT constructs with these groups (through a modified questionnaire) is feasible and acceptable.

Conclusions

The process of engaging end users in the design process provided valuable insights and will help to ensure that the DITETM app continues to address the needs of both the Deaf community and BIM interpreters in Malaysia.

Geraniin Ameliorates Hypertensive Vascular Remodelling in a Diet-Induced Obese Animal Model through Antioxidant and Anti-Inflammatory Effects

Geraniin, an ellagitannin, has shown a potent blood pressure-lowering effect in vivo. Therefore, this study aims to further characterize the ability of geraniin to attenuate hypertensive vascular dysfunction, a key feature of cardiovascular disease (CVD) development. Hypertension was induced in male Sprague-Dawley rats through feeding a high-fat diet (HFD) for eight weeks, followed by oral administration of 25 mg/kg/day geraniin for four weeks. The parameters of vascular dysfunction such as the structure and function of blood vessels as well as the vascular oxidative stress and inflammation were evaluated. The outcomes of geraniin-treated rats were compared with those of untreated rats on either a normal diet (ND) or HFD and with HFD-fed rats treated with captopril (40 mg/kg/day). We found that geraniin supplementation effectively ameliorated HFD-induced hypertension and abnormal remodelling of the thoracic aorta by suppressing excessive vascular superoxide (O₂^-) radical generation and overexpression of pro-inflammatory mediators in the circulating leukocytes. Furthermore, compared to the ND-fed rats, geraniin also independently promoted the significant enlargement of the thoracic aortic lumen for blood pressure reduction. Notably, the vascular benefits of geraniin were comparable to that of captopril. Collectively, these data suggest that geraniin can mitigate hypertensive vascular remodelling caused by overnutrition, which potentially abrogates the further development of CVDs.

Diet Gut Microbiota Axis in Pregnancy: A Systematic Review of Recent Evidence

PURPOSE OF REVIEW

Although gut microbiota have been associated with the etiology of some diseases, the influence of foods on gut microbiota, especially among pregnant women, remains unclear. Hence, a systematic review was performed to investigate the association between diet and gut microbiota and their influence on metabolic health in pregnant women.

RECENT FINDINGS

We performed the systematic review using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 protocol to investigate the association between diet and gut microbiota and their influence on metabolic role in pregnant women. Five databases were searched for relevant peer-reviewed articles published in English since 2011. Two-staged screening of 659 retrieved records resulted in the inclusion of 10 studies. The collated findings suggested associations between nutrient intakes and four key microbes: Collinsella, Lachnospira, Sutterella, Faecalibacterium, and the Firmicutes/Bacteroidetes ratio in pregnant women. Dietary intakes in pregnancy were found to modify the gut microbiota and positively influence the cell metabolism in pregnant women. This review, however, emphasizes the importance of conducting well-designed prospective cohorts to investigate the role of changes in dietary intakes within the pregnancy and the influence of such changes on gut microbiota.

Myricetin derivative-rich fraction from Syzygium malaccense prevents high-fat diet-induced obesity, glucose intolerance and oxidative stress in C57BL/6J mice

AIM

A high-fat diet (HFD) can lead to obesity and related metabolic disorders. This study evaluated the preventive efficacy of myricetin derivative-rich fraction (MD) from Syzygium malaccense leaf extract against HFD-induced obesity, hyperglycaemia, and oxidative stress in C57BL/6J mice.

METHODS

HFD-fed mice were administered MD (50 mg/kg, 100 mg/kg, and 150 mg/kg) or 2 mg/kg metformin (positive control) orally for 16 weeks. Normal diet and HFD-fed control groups received normal saline.

RESULTS

MD dose of 50 mg/kg was better than 100 mg/kg and 150 mg/kg in significantly reducing weight-gain, glucose intolerance, insulin resistance, lipid accumulation in liver and kidney, and improving the serum lipid profile. Lowered protein carbonyls and lipid hydroperoxides in urine and tissue homogenates and elevated reduced glutathione, ferric reducing antioxidant power (FRAP), and Trolox equivalent antioxidant capacity (TEAC) levels in tissue homogenates indicated amelioration of oxidative stress.

CONCLUSION

MD has therapeutic value in the prevention and management of obesity, hyperglycaemia, and oxidative stress.

Protease-targeting peptide-functionalized porous silicon nanoparticles for cancer fluorescence imaging

Background: Porous silicon (pSi) nanoparticles (NPs) functionalized with suitable targeting ligands are now established cancer bioimaging agents and drug-delivery platforms. With growing interest in peptides as tumor-targeting ligands, much work has focused on the use of various peptides in combination with pSi NPs for cancer theranostics. Here, the authors investigated the targeting potential of pSi NPs functionalized with two types of peptide, a linear 10-mer peptide and its branched (Y-shaped) equivalent, that respond to legumain activity in tumor cells. Results: In vitro experiments established that the linear peptide-pSi NP conjugate had better aqueous stability under tumor conditions and higher binding efficiency (p < 0.001) toward legumain-expressing cells such as RAW 264.7 cells compared with that of its branched equivalent. In vivo studies (analyzed using ex vivo fluorescence) with the linear peptide-pSi NP formulation using a syngeneic mouse model of breast cancer showed a higher accumulation (p > 0.05) of linear peptide-conjugated pSi NPs in the tumor site within 4 h compared with nonconjugated pSi NPs. These results suggest that the linear peptide-pSi NP formulation is a nontoxic, stable and efficient fluorescence bioimaging agent and potential drug-delivery platform.

Communication methods between physicians and Deaf patients: A scoping review

OBJECTIVE

Deaf individuals often face communication challenges within healthcare settings. Given the importance of the role played by physicians in shaping patients' health outcomes, it is paramount to explore Deaf patient-physician interactions. This research aims to explore (1) the existing communication support and (2) the factors influencing its usage in medical consultations with Deaf patients.

METHODS

A scoping review was carried out and adhered to the Preferred Reporting System for Meta-Analysis. A comprehensive search strategy of four databases; PubMed, Medline, CINAHL Plus and Scopus, from January 2011 to June 2021 was applied. Thematic analysis was used to analyse the data.

RESULTS

Ten journal articles were included, and four themes were identified; patient experiences using communication methods, practitioners' cultural competence in Deaf culture, inherent challenges of communication methods, and extrinsic factors. Professional interpreters are often regarded as the preferred modality of communication but writing and lip-reading were commonly used in healthcare settings, with video remote interpreting the least common.

CONCLUSION

Healthcare professionals need to appreciate the heterogeneity of Deaf patients and their communication methods and adopt a more person-centred approach.

PRACTICE IMPLICATIONS

This review provides up-to-date insight on Deaf patient-physician interactions and provisional recommendations for practice, education and policy.

The Oral, Gut Microbiota and Cardiometabolic Health of Indigenous Orang Asli Communities

The Orang Asli (OA) of Malaysia have been relatively understudied where little is known about their oral and gut microbiomes. As human health is closely intertwined with the human microbiome, this study first assessed the cardiometabolic health in four OA communities ranging from urban, rural to semi-nomadic hunter-gatherers. The urban Temuan suffered from poorer cardiometabolic health while rural OA communities were undergoing epidemiological transition. The oral microbiota of the OA were characterised by sequencing the V4 region of the 16S rRNA gene. The OA oral microbiota were unexpectedly homogenous, with comparably low alpha diversity across all four communities. The rural Jehai and Temiar PP oral microbiota were enriched for uncharacterised bacteria, exhibiting potential for discoveries. This finding also highlights the importance of including under-represented populations in large cohort studies. The Temuan oral microbiota were also elevated in opportunistic pathogens such as Corynebacterium, Prevotella, and Mogibacterium, suggesting possible oral dysbiosis in these urban settlers. The semi-nomadic Jehai gut microbiota had the highest alpha diversity, while urban Temuan exhibited the lowest. Rural OA gut microbiota were distinct from urban-like microbiota and were elevated in bacteria genera such as Prevotella 2, Prevotella 9, Lachnospiraceae ND3007, and Solobacterium. Urban Temuan microbiota were enriched in Odoribacter, Blautia, Parabacetroides, Bacteroides and Ruminococcacecae UCG-013. This study brings to light the current health trend of these indigenous people who have minimal access to healthcare and lays the groundwork for future, in-depth studies in these populations.

Health Care Needs of Deaf Signers: The Case for Culturally Competent Health Care Providers

There is a need for culturally competent health care providers (HCPs) to provide care to deaf signers, who are members of a linguistic and cultural minority group. Many deaf signers have lower health literacy levels due to deprivation of incidental learning opportunities and inaccessibility of health-related materials, increasing their risk for poorer health outcomes. Communication barriers arise because HCPs are ill-prepared to serve this population, with deaf signers reporting poor-quality interactions. This has translated to errors in diagnosis, patient nonadherence, and ineffective health information, resulting in mistrust of the health care system and reluctance to seek treatment. Sign language interpreters have often not received in-depth medical training, compounding the dynamic process of medical interpreting. HCPs should thus become more culturally competent, empowering them to provide cultural- and language-concordant services to deaf signers. HCPs who received training in cultural competency showed increased knowledge and confidence in interacting with deaf signers. Similarly, deaf signers reported more positive experiences when interacting with medically certified interpreters, HCPs with sign language skills, and practitioners who made an effort to improve communication. However, cultural competency programs within health care education remain inconsistent. Caring for deaf signers requires complex, integrated competencies that need explicit attention and practice repeatedly in realistic, authentic learning tasks ordered from simple to complex. Attention to the needs of deaf signers can start early in the curriculum, using examples of deaf signers in lectures and case discussions, followed by explicit discussions of Deaf cultural norms and the potential risks of low written and spoken language literacy. Students can subsequently engage in role plays with each other or representatives of the local signing deaf community. This would likely ensure that future HCPs are equipped with the knowledge and skills necessary to provide appropriate care and ensure equitable health care access for deaf signers.

Feasibility and Acceptability of a Dietary Intervention to Reduce Salt Intake and Increase High-Nitrate Vegetable Consumption in Malaysian Middle-Aged and Older Adults with Elevated Blood Pressure: Findings from the DePEC-Nutrition Trial

The DePEC-Nutrition trial is a complex dietary and behavioural intervention of salt intake reduction combined with increased high-nitrate vegetable consumption among Malaysian middle-aged and older adults with elevated blood pressure. This study aimed to assess the feasibility and acceptability of the trial. Participants were recruited from the South East Asia Community Observatory (SEACO) database and randomised into one of four groups: (1) low salt; (2) high-nitrate vegetable; (3) combined high-nitrate vegetable and low salt; and (4) control. The intervention included a combination of group counselling sessions, information booklets, reinforcement videos and text messages to modify dietary behaviour. The primary outcomes evaluated were the measures of feasibility and acceptability of (1) recruitment, follow-up attendance and retention; (2) data collection procedures and clinical outcome measures; and (3) individual and combined multi-modal dietary interventions. A total of 74 participants were recruited, and the 10-month retention rate was 73%. Data collection procedures were acceptable with minimal missing data. All intervention strategies were feasible and acceptable, with group counselling being the most acceptable strategy. This study provides important insights into improving the screening process of participants, facilitating their access to the research facilities and refining the measurement protocols and dietary recommendations, which are instrumental in formulating the design of a full-scale definitive DePEC-Nutrition trial.

Role of P34S, G169R, R296C, and S486T Substitutions in Ligand Access and Catalysis for Cytochrome P450 2D6 Allelic Variants CYP2D6*14A and CYP2D6*14B

BACKGROUND

Genetic polymorphism of cytochrome P450 (CYP) contributes to variability in drug metabolism, clearance, and response. This study aimed to investigate the functional and molecular basis for altered ligand binding and catalysis in CYP2D6*14A and CYP2D6*14B, two unique alleles common in the Asian population.

METHODS

CYP proteins expressed in Escherichia coli were studied using the substrate 3-cyano-7- ethoxycoumarin (CEC) and inhibitor probes (quinidine, fluoxetine, paroxetine, terbinafine) in the enzyme assay. Computer modelling was additionally used to create three-dimensional structures of the CYP2D6*14 variants.

RESULTS

Kinetics data indicated significantly reduced intrinsic clearance in CYP2D6*14 variants, suggesting that P34S, G169R, R296C, and S486T substitutions worked cooperatively to alter the conformation of the active site that negatively impacted the deethylase activity of CYP2D6. For the inhibition studies, IC50 values decreased in quinidine, paroxetine, and terbinafine but increased in fluoxetine, suggesting a varied ligand-specific susceptibility to inhibition. Molecular docking further demonstrated the role of P34S and R296C in altering access channel dimensions, thereby affecting ligand access and binding and subsequently resulting in varied inhibition potencies.

CONCLUSION

In summary, the differential selectivity of CYP2D6*14 variants for the ligands (substrate and inhibitor) was governed by the alteration of the active site and access channel architecture induced by the natural mutations found in the alleles.

The Modulation of Gut Microbiota Composition in the Pathophysiology of Gestational Diabetes Mellitus: A Systematic Review

Simple Summary

Recent studies have placed a great deal of emphasis on the importance of the microbiome, especially the link between the alteration of gut microbiota and multiple associated diseases. Gut microbiota changes in pregnancy have a significant impact on metabolic function and may contribute to gestational diabetes mellitus (GDM). Although GDM carries long-term health risks that affect women, there are also significant short- and severe long-term consequences for the offspring. Regardless, there is a notable lack of research focusing on the impact of prominent microorganisms involved in the development of GDM. A comprehensive review was conducted to gather relevant data on the types of microorganisms that have been associated with GDM. The review found that certain microorganisms impact the onset and progression of GDM during pregnancy. Several bacterial strains associated with GDM are influenced by a diet high in fat and low in fiber. Therefore, integrating the idea of a microbiome-based individualized dietary intervention into gestational diabetes management may be incredibly beneficial.

Abstract

General gut microbial dysbiosis in diabetes mellitus, including gestational diabetes mellitus (GDM), has been reported in a large body of literature. However, evidence investigating the association between specific taxonomic classes and GDM is lacking. Thus, we performed a systematic review of peer-reviewed observational studies and trials conducted among women with GDM within the last ten years using standard methodology. The National Institutes of Health (NIH) quality assessment tools were used to assess the quality of the included studies. Fourteen studies investigating microbial interactions with GDM were found to be relevant and included in this review. The synthesis of literature findings demonstrates that Bacteroidetes, Proteobacteria, Firmicutes, and Actinobacteria phyla, such as Desulfovibrio, Ruminococcaceae, P. distasonis, Enterobacteriaceae, Collinsella, and Prevotella, were positively associated with GDM. In contrast, Bifidobacterium and Faecalibacterium, which produce butyrate, are negatively associated with GDM. These bacteria were associated with inflammation, adiposity, and glucose intolerance in women with GDM. Lack of good diet management demonstrated the alteration of gut microbiota and its impact on GDM glucose homeostasis. The majority of the studies were of good quality. Therefore, there is great potential to incorporate personalized medicine targeting microbiome modulation through dietary intervention in the management of GDM.

Flavonoid Composition and Pharmacological Properties of Elaeis guineensis Jacq. Leaf Extracts: A Systematic Review

The oil palm tree (Elaeis guineensis Jacq.) originates from West and Central Africa, and it is cultivated in Malaysia for its oil-producing fruits. Malaysia is the world’s second largest palm oil producer and the world’s largest exporter to date. Consequently, the Malaysian oil palm industry constantly generates a huge amount of biomass with the major contributor being the leaves. A large percentage of these leaves remain underutilized, making them a promising source of raw materials that can be converted into value-added products. The present review summarizes and discusses the flavonoid composition, total phenolic and flavonoid content, and the in vitro and in vivo pharmacological properties exhibited by the extracts of the leaves of E. guineensis. The purpose of this systematic review is to highlight the potential of valorizing the leaf extracts of the oil palm tree as pharmaceutical and cosmeceutical agents.

Improving oral bioavailability of medicinal herbal compounds through lipid-based formulations - A Scoping Review

BACKGROUND

Although numerous medicinal herbal compounds demonstrate promising therapeutic potential, their clinical application is often limited by their poor oral bioavailability. To circumvent this barrier, various lipid-based herbal formulations have been developed and trialled with promising experimental results.

PURPOSE

This scoping review aims to describe the effect of lipid-based formulations on the oral bioavailability of herbal compounds.

METHODS

A systematic search was conducted across three electronic databases (Medline, Embase and Cochrane Library) between January 2010 and January 2021 to identify relevant studies. The articles were rigorously screened for eligibility. Data from eligible studies were then extracted and collated for synthesis and descriptive analysis using Covidence.

RESULTS

A total of 109 studies were included in the present review: 105 animal studies and four clinical trials. Among the formulations investigated, 50% were emulsions, 34% lipid particulate systems, 12% vesicular systems, and 4% were other types of lipid-based formulations. Within the emulsion system classification, self-emulsifying drug delivery systems were observed to produce the best improvements in oral bioavailability, followed by mixed micellar formulations. The introduction of composite lipid-based formulations and the use of uncommon surfactants such as sodium oleate in emulsion preparation was shown to consistently enhance the bioavailability of herbal compounds with poor oral absorption. Interestingly, the lipid-based formulations of magnesium lithospermate B and Pulsatilla chinensis produced an absolute bioavailability greater than 100% indicating the possibility of prolonged systemic circulation. With respect to chemical conjugation, D-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) was the most frequently used and significantly improved the bioavailability of its phytoconstituents.

CONCLUSION

Our findings suggest that there is no distinct lipid-based formulation superior to the other. Bioavailability improvements were largely dependent on the nature of the phytoconstituents. This scoping review, however, provided a detailed summary of the most up-to-date evidence on phytoconstituents formulated into lipid preparations and their oral bioavailability. We conclude that a systematic review and meta-analysis between bioavailability improvements of individual phytoconstituents (such as kaempferol, morin and myricetin) in various lipid-based formulations will provide a more detailed association. Such a review will be highly beneficial for both researchers and herbal manufacturers.

In vitro inhibitory effects of glucosamine, chondroitin and diacerein on human hepatic CYP2D6

OBJECTIVES

Glucosamine, chondroitin and diacerein are natural compounds commonly used in treating osteoarthritis. Their concomitant intake may trigger drug-natural product interactions. Cytochrome P450 (CYP) has been implicated in such interactions. Cytochrome P450 2D6 (CYP2D6) is a major hepatic CYP involved in metabolism of 25% of the clinical drugs. This study aimed to investigate the inhibitory effect of these antiarthritic compounds on CYP2D6.

METHODS

CYP2D6 was heterologously expressed in Escherichia coli. CYP2D6-antiarthritic compound interactions were studied using in vitro enzyme kinetics assay and molecular docking.

RESULTS

The high-performance liquid chromatography (HPLC)-based dextromethorphan O-demethylase assay was established as CYP2D6 marker. All glucosamines and chondroitins weakly inhibited CYP2D6 (IC₅₀ values >300 µM). Diacerein exhibited moderate inhibition with IC₅₀ and K _i values of 34.99 and 38.27 µM, respectively. Its major metabolite, rhein displayed stronger inhibition potencies (IC₅₀=26.22 μM and K _i =32.27 μM). Both compounds exhibited mixed-mode of inhibition. In silico molecular dockings further supported data from the in vitro study. From in vitro-in vivo extrapolation, rhein presented an area under the plasma concentration-time curve (AUC) ratio of 1.5, indicating low potential to cause in vivo inhibition.

CONCLUSIONS

Glucosamine, chondroitin and diacerein unlikely cause clinical interaction with the drug substrates of CYP2D6. Rhein, exhibits only low potential to cause in vivo inhibition.

In vitro inhibitory effects of glucosamine, chondroitin and diacerein on human hepatic CYP2D6

OBJECTIVES

Glucosamine, chondroitin and diacerein are natural compounds commonly used in treating osteoarthritis. Their concomitant intake may trigger drug-natural product interactions. Cytochrome P450 (CYP) has been implicated in such interactions. Cytochrome P450 2D6 (CYP2D6) is a major hepatic CYP involved in metabolism of 25% of the clinical drugs. This study aimed to investigate the inhibitory effect of these antiarthritic compounds on CYP2D6.

METHODS

CYP2D6 was heterologously expressed in Escherichia coli. CYP2D6-antiarthritic compound interactions were studied using in vitro enzyme kinetics assay and molecular docking.

RESULTS

The high-performance liquid chromatography (HPLC)-based dextromethorphan O-demethylase assay was established as CYP2D6 marker. All glucosamines and chondroitins weakly inhibited CYP2D6 (IC50 values >300 µM). Diacerein exhibited moderate inhibition with IC50 and K i values of 34.99 and 38.27 µM, respectively. Its major metabolite, rhein displayed stronger inhibition potencies (IC50=26.22 μM and K i =32.27 μM). Both compounds exhibited mixed-mode of inhibition. In silico molecular dockings further supported data from the in vitro study. From in vitro-in vivo extrapolation, rhein presented an area under the plasma concentration-time curve (AUC) ratio of 1.5, indicating low potential to cause in vivo inhibition.

CONCLUSIONS

Glucosamine, chondroitin and diacerein unlikely cause clinical interaction with the drug substrates of CYP2D6. Rhein, exhibits only low potential to cause in vivo inhibition.

Gestational Diabetes Mellitus in Southeast Asia: A Scoping Review

A rapid increase in the prevalence of gestational diabetes mellitus (GDM) has been associated with various factors such as urbanization, lifestyle changes, adverse hyperglycemic intrauterine environment, and the resulting epigenetic changes. Despite this, the burden of GDM has not been well-assessed in Southeast Asia. We comprehensively reviewed published Southeast Asian studies to identify the current research trend in GDM in this region. Joanna Briggs Institute’s methodology was used to guide the scoping review. The synthesis of literature findings demonstrates almost comparable clinical evidence in terms of risk factors and complications, challenges presented in diagnosing GDM, and its disease management, given the similarities of the underlying population characteristics in Southeast Asia. Evidence suggests that a large proportion of GDM risk in women may be preventable by lifestyle modifications. However, the GDM burden across countries is expected to rise, given the heterogeneity in screening approaches and diagnostic criteria, mainly influenced by economic status. There is an urgent need for concerted efforts by government and nongovernmental sectors to implement national programs to prevent, manage, and monitor the disease.

Amelioration of high-fat diet-induced obesity and its associated complications by a myricetin derivative-rich fraction from Syzygium malaccense in C57BL/6J mice

Obesity is a driving factor in the onset of metabolic disorders. This study aims to investigate the effects of the myricetin derivative-rich fraction (MD) from Syzygium malaccense leaf extract on high-fat diet (HFD)-induced obesity and its associated complications and its influence on uncoupling protein-1 (UCP-1) and gut microbiota in C57BL/6J mice. Mice were randomly assigned into four groups (n = 6) and given a normal diet (ND) or high-fat diet (HFD) for 10 weeks to induce obesity. The HFD groups (continued with HFD) were administered 50 mg kg-1 MD (treatment), 50 mg kg-1 metformin (positive control) and normal saline (HFD and ND controls) daily for four weeks via oral gavage. The ten-week HFD-feeding resulted in hyperglycemia and elevated urinary oxidative indices. The subsequent MD administration caused significant weight reduction without appetite suppression and amelioration of insulin resistance, steatosis and dyslipidemia. Besides, MD significantly reduced lipid hydroperoxides and protein carbonyls in tissue homogenates and urine and elevated Trolox equivalent antioxidant capacity (TEAC), ferric reducing antioxidant power (FRAP) and reduced glutathione (GSH) and thus, alleviated oxidative stress. The weight reduction was correlated with downregulation of inflammatory markers and the increased UCP-1 level, suggesting weight loss plausibly through thermogenesis. The Akkermansia genus (reflects improved metabolic status) in the HFD50 group was more abundant than that in the HFD group while the non-enzymatic antioxidant markers were strongly associated with UCP-1. In conclusion, MD ameliorates obesity and its related complications possibly via the upregulation of UCP-1 and increased abundance of Akkermansia genus and is promising as a therapeutic agent in the treatment of obesity and its associated metabolic disorders.

Design suggestions for an mHealth app to facilitate communication between pharmacists and the Deaf: perspective of the Deaf community (HEARD Project)

BACKGROUND

Deaf and hard-of-hearing (DHH) patients have trouble communicating with community pharmacists and accessing the healthcare system. This study explored the views on a proposed mobile health (mHealth) app in terms of design and features, that will be able to bridge the communication gap between community pharmacists and DHH patients.

METHODS

A community-based participatory research method was utilized. Two focus group discussions (FGDs) were conducted in Malaysian sign language (BIM) with a total of 10 DHH individuals. Respondents were recruited using purposive sampling. Video-recordings were transcribed and analyzed using a thematic approach.

RESULTS

Two themes emerged: (I) challenges and scepticism of the healthcare system; and (II) features of the mHealth app. Respondents expressed fears and concerns about accessing healthcare services, and stressed on the need for sign language interpreters. There were also concerns about data privacy and security. With regard to app features, the majority preferred videos instead of text to convey information about their disease and medication, due to their lower literacy levels.

CONCLUSIONS

For an mHealth app to be effective, app designers must ensure the app is individualised according to the cultural and linguistic diversity of the target audience. Pharmacists should also educate patients on the potential benefits of the app in terms of assisting patients with their medicine-taking.

Pleiotropic ameliorative effects of ellagitannin geraniin against metabolic syndrome induced by high-fat diet in rats

OBJECTIVES

Metabolic syndrome (MetS), a multiplex risk factor for cardiovascular disease and type 2 diabetes, is increasingly prevalent worldwide. Ellagitannin geraniin, a polyphenol found in the rind of rambutan (Nephelium lappaceum), has demonstrated therapeutic effects against metabolism dysfunction. The aim of this study was to characterize the metabolic effects and possible mechanism of geraniin in rats with MetS induced by a high-fat diet (HFD).

METHODS

MetS was induced in Sprague Dawley rats on an HFD, followed by a daily oral gavage of geraniin (25 mg/kg) for 4 wk. The outcomes of geraniin-treated rats were compared with those of untreated rats on either a control diet or an HFD and with rats with MetS treated with metformin on a daily basis (200 mg/kg).

RESULTS

The supplementation of geraniin ameliorated multiple metabolic abnormalities caused by HFD, including hypertension, impaired glucose and lipid metabolism, ectopic fat deposition in the visceral fat and liver, and disturbed antioxidant mechanism and inflammatory response. The benefits conferred by geraniin were comparable to metformin. Transcriptomic analysis revealed a profound influence of geraniin on the hepatic expression profiles. The lipid and steroid metabolic processes that were aberrantly activated by HFD were suppressed by geraniin. Based on the differential transcriptomes, geraniin also exerted a significant modulatory effect on the expression of mitochondrial genes, potentially influencing the mitochondrial activity and leading to the observed beneficial effects.

CONCLUSION

Geraniin supplementation mitigated metabolic anomalies of MetS in rats, making it an attractive drug candidate for further investigation.

The insulin-sensitising properties of the ellagitannin geraniin and its metabolites from Nephelium lappaceum rind in 3T3-L1 cells

In this study, the insulin-like and insulin sensitising effects of the ellagitannins geraniin, corilagin, ellagic acid, gallic acid and Nephelium lappaceum rind extract in 3T3-L1 adipocytes was investigated. It was observed that non-toxic concentrations of geraniin and its metabolites (0.2-20 μM) and N. lappaceum extract (0.2-20 μg/mL) exhibited insulin-like properties in the absence of insulin and insulin-sensitising properties in the presence of insulin particularly with regards to glucose uptake in 3T3-L1 adipocytes. The compounds were further able to promote adipocyte differentiation and may be involved in the inhibition of lipolysis in 3T3-L1 adipocytes in the presence of insulin. However further study into the molecular mechanisms of action of these compounds need to be carried out to better understand the potential of these compounds/extracts to act as therapeutic agents for hyperglycaemia associated with diabetes mellitus and obesity.

The Molecular and Enzyme Kinetic Basis for Altered Activity of Three Cytochrome P450 2C19 Variants Found in the Chinese Population

BACKGROUND

There is a large inter-individual variation in cytochrome P450 2C19 (CYP2C19) activity. The variability can be caused by the genetic polymorphism of CYP2C19 gene. This study aimed to investigate the molecular and kinetics basis for activity changes in three alleles including CYP2C19*23, CYP2C19*24 and CYP2C19*25found in the Chinese population.

METHODS

The three variants expressed by bacteria were investigated using substrate (omeprazole and 3- cyano-7-ethoxycoumarin[CEC]) and inhibitor (ketoconazole, fluoxetine, sertraline and loratadine) probes in enzyme assays along with molecular docking.

RESULTS

All alleles exhibited very low enzyme activity and affinity towards omeprazole and CEC (6.1% or less in intrinsic clearance). The inhibition studies with the four inhibitors, however, suggested that mutations in different variants have a tendency to cause enhanced binding (reduced IC50 values). The enhanced binding could partially be explained by the lower polar solvent accessible surface area of the inhibitors relative to the substrates. Molecular docking indicated that G91R, R335Q and F448L, the unique mutations in the alleles, have caused slight alteration in the substrate access channel morphology and a more compact active site cavity hence affecting ligand access and binding. It is likely that these structural alterations in CYP2C19 proteins have caused ligand-specific alteration in catalytic and inhibitory specificities as observed in the in vitro assays.

CONCLUSION

This study indicates that CYP2C19 variant selectivity for ligands was not solely governed by mutation-induced modifications in the active site architecture, but the intrinsic properties of the probe compounds also played a vital role.

Protective effect of myricetin derivatives from Syzygium malaccense against hydrogen peroxide-induced stress in ARPE-19 cells

PURPOSE

Oxidative stress is implicated in the etiology of diabetes and its debilitating complications, such as diabetic retinopathy (DR). Various flavonoids have been reported to be useful in reducing DR progression. Myricetin derivatives (F2) isolated from leaf extract of Syzygium malaccense have the potential to serve as functional food as reported previously. The present study was performed with the aim of determining the antioxidant potential and protective effect of myricetin derivatives (F2) isolated from leaf extract of S. malaccense against glucose oxidase (GO)-induced hydrogen peroxide (H₂O₂) production that causes oxidative stress in ARPE-19 (RPE) cells.

METHODS

Antioxidant properties were assessed through various radical (DPPH, ABTS, and nitric oxide) scavenging assays and determination of total phenolic content and ferric reducing antioxidant power level. ARPE-19 cells were preincubated with samples before the addition of GO (to generate H₂O₂). Cell viability, change in intracellular reactive oxygen species (ROS), H₂O₂ levels in cell culture supernatant, and gene expression were assessed.

RESULTS

F2 showed higher antioxidant levels than the extract when assessed for radical scavenging activities and ferric reducing antioxidant power. F2 protected the ARPE-19 cells against GO-H₂O₂-induced oxidative stress by reducing the production of H₂O₂ and intracellular reactive oxygen species. This was achieved by the activation of nuclear factor erythroid 2-related factor 2 (Nrf2/NFE2L2) and superoxide dismutase (SOD2), as well as downregulation of nitric oxide producer (NOS2) at the transcriptional level.

CONCLUSIONS

The results showed that myricetin derivatives from S. malaccense have the capacity to exert considerable exogenous antioxidant activities and stimulate endogenous antioxidant activities. Therefore, these derivatives have excellent potential to be developed as therapeutic agents for managing DR.

A qualitative study on the design and development of an mHealth app to facilitate communication with the Deaf community: perspective of community pharmacists

PURPOSE

This study prepares the groundwork on the potential design and development of a mobile health (mHealth) app that will be able to bridge the communication gap between pharmacists and patients who are Deaf and Hard of Hearing (DHoH).

PATIENTS AND METHODS

A focus group discussion was conducted with 12 community pharmacists. Participants were recruited using snowball sampling. Audio-recordings were transcribed verbatim, and analyzed using a thematic approach.

RESULTS

Three themes were apparent: 1) suggestions for app design and content, 2) perceived benefits of the app, and 3) potential challenges related to the app. Participants believed the app would be able to facilitate and improve communication, and hence relationship, between pharmacists and the DHoH. Potential challenges of the app were highlighted, such as the need for manpower to manage the app, and its cost to this group of economically disadvantaged people. There were also concerns about privacy and security.

CONCLUSIONS

This study allowed community pharmacists, one of the end-users of the app, to provide feedback on the contents and design of the app, which would allow them to provide pharmaceutical care services to patients who are DHoH, and better serve them. Potential benefits and challenges of the app were also identified. Undoubtedly, through the mHealth app, community pharmacists will be better equipped to serve and communicate with the DHoH, and this will hopefully translate to improved health outcomes in these patients.

Cytochrome P450 2C9-natural antiarthritic interactions: Evaluation of inhibition magnitude and prediction from in vitro data

Many dietary supplements are promoted to patients with osteoarthritis (OA) including the three naturally derived compounds, glucosamine, chondroitin and diacerein. Despite their wide spread use, research on interaction of these antiarthritic compounds with human hepatic cytochrome P450 (CYP) enzymes is limited. This study aimed to examine the modulatory effects of these compounds on CYP2C9, a major CYP isoform, using in vitro biochemical assay and in silico models. Utilizing valsartan hydroxylase assay as probe, all forms of glucosamine and chondroitin exhibited IC₅₀ values beyond 1000 μM, indicating very weak potential in inhibiting CYP2C9. In silico docking postulated no interaction with CYP2C9 for chondroitin and weak bonding for glucosamine. On the other hand, diacerein exhibited mixed-type inhibition with IC₅₀ value of 32.23 μM and K_i value of 30.80 μM, indicating moderately weak inhibition. Diacerein's main metabolite, rhein, demonstrated the same mode of inhibition as diacerein but stronger potency, with IC₅₀ of 6.08 μM and K_i of 1.16 μM. The docking of both compounds acquired lower CDOCKER interaction energy values, with interactions dominated by hydrogen and hydrophobic bondings. The ranking with respect to inhibition potency for the investigated compounds was generally the same in both in vitro enzyme assay and in silico modeling with order of potency being diacerein/rhein > various glucosamine/chondroitin forms. In vitro-in vivo extrapolation of inhibition kinetics (using 1 + [I]/K_i ratio) demonstrated negligible potential of diacerein to cause interaction in vivo, whereas rhein was predicted to cause in vivo interaction, suggesting potential interaction risk with the CYP2C9 drug substrates.

Translation of the 5D Itching Scale from English to Malay, and Its Validation among Patients with Chronic Kidney Disease in Malaysia

Introduction

Several tools have been developed to assess the severity of pruritus. In Malaysia, no tool has been validated to assess pruritus in patients with chronic kidney disease (CKD). Therefore, the aim of our study was to validate the Malay 5D itching scale (M5D-IS) among patients with CKD in Malaysia.

Method

The English version of the 5D-IS was translated into Malay according to International Guidelines. Face and content validity was determined by an expert panel and pilot tested in patients with end-stage renal disease (ESRD). The M5D-IS was then validated in a tertiary hospital in Malaysia from May to June 2016. We recruited patients with (i.e., patients with ESRD) and without pruritus (i.e., patients with stage 1–3 CKD) (to determine if the M5D-IS could discriminate between the two groups), and administered the M5D-IS at baseline and 2 weeks later. Exploratory factor analysis was used to examine the construct validity. Internal consistency was assessed using Cronbach’s alpha and intraclass correlation coefficient was calculated to assess the reliability of the instrument.

Results

A total of 70 participants were recruited (response rate = 100%). The majority were males (51.4%) and Malay (67.1%). Exploratory factor analysis revealed that the 5D-IS had 2-factor loadings: “daily routine activity” and “pattern of itching,” which explained 77.7% of the variance. The overall score of the M5D-IS, as well as for each domain, was significantly worse in participants with pruritus (9.83 ± 0.35), compared to those without pruritus (5.51 ± 0.93, p < 0.001). The overall Cronbach’s alpha for the M5D-IS was (0.861), indicating adequate internal consistency. At test–retest, the intraclass correlation coefficient was significantly correlated.

Conclusion

The M5D-IS was found to be a valid and reliable instrument to assess pruritus among patients with CKD in Malaysia.

Fermentation Conditions that Affect Clavulanic Acid Production in Streptomyces clavuligerus: A Systematic Review

The β-lactamase inhibitor, clavulanic acid is frequently used in combination with β-lactam antibiotics to treat a wide spectrum of infectious diseases. Clavulanic acid prevents drug resistance by pathogens against these β-lactam antibiotics by preventing the degradation of the β-lactam ring, thus ensuring eradication of these harmful microorganisms from the host. This systematic review provides an overview on the fermentation conditions that affect the production of clavulanic acid in the firstly described producer, Streptomyces clavuligerus. A thorough search was conducted using predefined terms in several electronic databases (PubMed, Medline, ScienceDirect, EBSCO), from database inception to June 30th 2015. Studies must involve wild-type Streptomyces clavuligerus, and full texts needed to be available. A total of 29 eligible articles were identified. Based on the literature, several factors were identified that could affect the production of clavulanic acid in S. clavuligerus. The addition of glycerol or other vegetable oils (e.g., olive oil, corn oil) could potentially affect clavulanic acid production. Furthermore, some amino acids such as arginine and ornithine, could serve as potential precursors to increase clavulanic acid yield. The comparison of different fermentation systems revealed that fed-batch fermentation yields higher amounts of clavulanic acid as compared to batch fermentation, probably due to the maintenance of substrates and constant monitoring of certain entities (such as pH, oxygen availability, etc.). Overall, these findings provide vital knowledge and insight that could assist media optimization and fermentation design for clavulanic acid production in S. clavuligerus.

Streptomyces malaysiense sp. nov.: A novel Malaysian mangrove soil actinobacterium with antioxidative activity and cytotoxic potential against human cancer cell lines

Actinobacteria from the unique intertidal ecosystem of the mangroves are known to produce novel, bioactive secondary metabolites. A novel strain known as MUSC 136^T (=DSM 100712^T = MCCC 1K01246^T) which was isolated from Malaysian mangrove forest soil has proven to be no exception. Assessed by a polyphasic approach, its taxonomy showed a range of phylogenetic and chemotaxonomic properties consistent with the genus of Streptomyces. Phylogenetically, highest similarity was to Streptomyces misionensis NBRC 13063^T (99.6%) along with two other strains (>98.9% sequence similarities). The DNA–DNA relatedness between MUSC 136^T and these type strains ranged from 22.7 ± 0.5% to 46.5 ± 0.2%. Overall, polyphasic approach studies indicated this strain represents a novel species, for which the name Streptomyces malaysiense sp. nov. is proposed. The potential bioactivities of this strain were explored by means of antioxidant and cytotoxic assays. Intriguingly, MUSC 136^T exhibited strong antioxidative activities as evaluated by a panel of antioxidant assays. It was also found to possess high cytotoxic effect against HCT-116 cells, which probably mediated through altering p53 protein and intracellular glutathione levels. Chemical analysis of the extract using GC-MS further affirms that the strain produces chemopreventive related metabolites.

Streptomyces gilvigriseus sp. nov., a novel actinobacterium isolated from mangrove forest soil

A novel Streptomyces, strain MUSC 26(T), was isolated from mangrove soil at Tanjung Lumpur, Malaysia. The bacterium was observed to be Gram-positive and to form grayish yellow aerial and substrate mycelium on ISP 7 agar. A polyphasic approach was used to study the taxonomy of strain MUSC 26(T), which shows a range of phylogenetic and chemotaxonomic properties consistent with those of the members of the genus Streptomyces. The cell wall peptidoglycan was determined to contain LL-diaminopimelic acid. The predominant menaquinones were identified as MK-9 (H8) and MK-9(H6). The polar lipids detected were identified as diphosphatidylglycerol, phosphatidylinositol, phosphatidylethanolamine, hydroxyphosphatidylethanolamine, phosphatidylmethylethanolamine and hydroxyphosphatidylmethylethanolamine. The predominant cellular fatty acids (>10.0 %) were identified as anteiso-C15:0 (31.4 %), iso-C16:0 (16.3 %), iso-C15:0 (13.9 %) and anteiso-C17:0 (12.6 %). The cell wall sugars were found to be galactose, glucose, mannose, ribose and rhamnose. These results suggest that MUSC 26(T) should be placed within the genus Streptomyces. Phylogenetic analysis indicated that closely related strains include Streptomyces qinglanensis 172205(T) (96.5 % sequence similarity), S. sodiiphilus YIM 80305(T) (96.5 %) and S. rimosus subsp. rimosus ATCC 10970(T) (96.4 %). DNA-DNA relatedness values between MUSC 26(T) and closely related type strains ranged from 17.0 ± 2.2 to 33.2 ± 5.3 %. Comparison of BOX-PCR fingerprints indicated MUSC 26(T) presents a unique DNA profile. The DNA G+C content was determined to be 74.6 mol%. Based on this polyphasic study of MUSC 26(T), it is concluded that this strain represents a novel species, for which the name Streptomyces gilvigriseus sp. nov. is proposed. The type strain is MUSC 26(T) (=DSMZ 42173(T) = MCCC 1K00504(T)).

An effective ostrich oil bleaching technique using peroxide value as an indicator

Ostrich oil has been used extensively in the cosmetic and pharmaceutical industries. However, rancidity causes undesirable chemical changes in flavour, colour, odour and nutritional value. Bleaching is an important process in refining ostrich oil. Bleaching refers to the removal of certain minor constituents (colour pigments, free fatty acid, peroxides, odour and non-fatty materials) from crude fats and oils to yield purified glycerides. There is a need to optimize the bleaching process of crude ostrich oil prior to its use for therapeutic purposes. The objective of our study was to establish an effective method to bleach ostrich oil using peroxide value as an indicator of refinement. In our study, we showed that natural earth clay was better than bentonite and acid-activated clay to bleach ostrich oil. It was also found that 1 hour incubation at a 150 °C was suitable to lower peroxide value by 90%. In addition, the nitrogen trap technique in the bleaching process was as effective as the continuous nitrogen flow technique and as such would be the recommended technique due to its cost effectiveness.

Standardized extract of Syzygium aqueum: a safe cosmetic ingredient

Syzygium aqueum, a species in the Myrtaceae family, commonly called the water jambu is native to Malaysia and Indonesia. It is well documented as a medicinal plant, and various parts of the tree have been used in traditional medicine, for instance as an antibiotic. In this study, we show S. aqueum leaf extracts to have a significant composition of phenolic compounds, protective activity against free radicals as well as low pro-oxidant capability. Its ethanolic extract, in particular, is characterized by its excellent radical scavenging activity of EC(50) of 133 μg mL(-1) 1,1-diphenyl-2-picryl-hydrazyl (DPPH), 65 μg mL(-1) 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) and 71 μg mL(-1) (Galvinoxyl), low pro-oxidant capabilities and a phenolic content of 585-670 mg GAE g(-1) extract. The extract also displayed other activities, deeming it an ideal cosmetic ingredient. A substantial tyrosinase inhibition activity with an IC(50) of about 60 μg mL(-1) was observed. In addition, the extract was also found to have anti-cellulite activity tested for its ability to cause 98% activation of lipolysis of adipocytes (fat cells) at a concentration of 25 μg mL(-1). In addition, the extract was not cytotoxic to Vero cell lines up to a concentration of 600 μg mL(-1). Although various parts of this plant have been used in traditional medicine, this is the first time it has been shown to have cosmeceutical properties. Therefore, the use of this extract, alone or in combination with other active principles, is of interest to the cosmetic industry.

Synthesis and evaluation of affinity adsorbents for glycoproteins: an artificial lectin

A combination of rational design based on mimicking natural protein-carbohydrate interactions and solid-phase combinatorial chemistry has led to the identification of an affinity ligand which displays selectivity for the mannose moiety of glycoproteins. The ligand, denoted 18/18 and comprising a triazine scaffold bis-substituted with 5-aminoindan, has been synthesised in solution, characterised by TLC, 1H-NMR and MS. When immobilised to amine-derivatised agarose at concentrations >24 micromol/g moist weight gel, ligand 18/18 selectively binds glucose oxidase. The adsorbed enzyme was quantitatively eluted with 0.5 M alpha-D-methyl-mannoside and to a lesser extent with the equivalent glucoside. An investigation of the comparative retention times of saccharidic solutes showed that significant retardation was observed for alpha-D-mannose, mannobiose and mannan, with little or no evidence for selective retention of other saccharides, with the exception of alpha-L-fucose. Interestingly, alpha-L-fucose and alpha-D-mannose share an identical configuration of the hydroxyl groups on C-2, C-3 and C-4. Analysis of Scatchard plots from partition equilibrium studies on the interaction of glucose oxidase and the p-nitrophenyl-glycosides of D-mannose, D-glucose, L-fucose and D-galactose with immobilised 18/18 establish that the affinity constants (K(AX)) for the enzyme, the glycosides of mannose, glucose and fucose, and the p-nitrophenyl-galactoside are 4.3x10(5) M(-1), 1.9X10(4) M(-1) and 1.2x10(4) M(-1) respectively. 1H-NMR studies on the interaction of alpha-D-methyl-mannoside with ligand 18/18 in solution confirm the involvement of the hydroxyl group in the C-2 position. Molecular modelling suggests the formation of four hydrogen bonds between the hydroxyl groups at positions C-2, C-3 and C-4 of alpha-D-methyl-mannoside and the bridging and ring nitrogen atoms of the triazine scaffold, with aromatic stacking of a second ligand against the carbohydrate face. The greater specificity of ligand 18/18 for mannose and glucose than for galactose parallels that exhibited by concanavalin A.

Design, synthesis and characterisation of affinity ligands for glycoproteins

The concepts of rational design and solid phase combinatorial chemistry were used to develop affinity adsorbents for glycoproteins. A detailed assessment of protein-carbohydrate interactions was used to identify key residues that determine monosaccharide specificity, which were subsequently exploited as the basis for the synthesis of a library of glycoprotein binding ligands. The ligands were synthesised using solid phase combinatorial chemistry and were assessed for their sugar-binding ability with the glycoenzymes, glucose oxidase and RNase B. Partial and completely deglycosylated enzymes were used as controls. The triazine-based ligand, histamine/tryptamine (8/10) was identified as a putative glycoprotein binding ligand, since it displayed particular affinity for glucose oxidase and other mannosylated glycoproteins. Experiments with deglycosylated control proteins, specific eluants and retardation in the presence of competing sugars strongly suggest that the ligand binds the carbohydrate moiety of glucose oxidase rather than the protein itself.