Meng-Wong Taing

Mango fruit peel and flesh extracts affect adipogenesis in 3T3-L1 cells

Obesity is associated with many chronic disease states, such as diabetes mellitus, coronary disease and certain cancers, including those of the breast and colon. There is a growing body of evidence that links phytochemicals with the inhibition of adipogenesis and protection against obesity. Mangoes (Mangifera indica L.) are tropical fruits that are rich in a diverse array of bioactive phytochemicals. In this study, methanol extracts of peel and flesh from three archetypal mango cultivars; Irwin, Nam Doc Mai and Kensington Pride, were assessed for their effects on a 3T3-L1 pre-adipocyte cell line model of adipogenesis. High content imaging was used to assess: lipid droplets per cell, lipid droplet area per cell, lipid droplet integrated intensity, nuclei count and nuclear area per cell. Mango flesh extracts from the three cultivars did not inhibit adipogenesis; peel extracts from both Irwin and Nam Doc Mai, however, did so with the Nam Doc Mai extract most potent at inhibiting adipogenesis. Peel extract from Kensington Pride promoted adipogenesis. The inhibition of adipogenesis by Irwin (100 μg mL(-1)) and Nam Doc Mai peel extracts (50 and 100 μg mL(-1)) was associated with an increase in the average nuclear area per cell; similar effects were seen with resveratrol, suggesting that these extracts may act through pathways similar to resveratrol. These results suggest that differences in the phytochemical composition between mango cultivars may influence their effectiveness in inhibiting adipogenesis, and points to mango fruit peel as a potential source of nutraceuticals.

Mango (Mangifera indica L.) peel extract fractions from different cultivars differentially affect lipid accumulation in 3T3-L1 adipocyte cells

Plant phytochemicals are increasingly recognised as sources of bioactive molecules which may have potential benefit in many health conditions. In mangoes, peel extracts from different cultivars exhibit varying effects on adipogenesis in the 3T3-L1 adipocyte cell line. In this study, the effects of preparative HPLC fractions of methanol peel extracts from Irwin, Nam Doc Mai and Kensington Pride mangoes were evaluated. Fraction 1 contained the most hydrophilic components while subsequent fractions contained increasingly more hydrophobic components. High content imaging was used to assess mango peel fraction effects on lipid accumulation, nuclei count and nuclear area in differentiating 3T3-L1 cells. For all three mango cultivars, the more hydrophilic peel fractions 1-3 inhibited lipid accumulation with greater potency than the more hydrophobic peel fractions 4. For all three cultivars, the more lipophilic fraction 4 had concentrations that enhanced lipid accumulation greater than fractions 1-3 as assessed by lipid droplet integrated intensity. The potency of this fraction 4 varied significantly between cultivars. Using mass spectrometry, five long chain free fatty acids were detected in fraction 4; these were not present in any other peel extract fractions. Total levels varied between cultivars, with Irwin fraction 4 containing the highest levels of these free fatty acids. Lipophilic components appear to be responsible for the lipid accumulation promoting effects of some mango extracts and are the likely cause of the diverse effects of peel extracts from different mango cultivars on lipid accumulation.

Mango Fruit Extracts Differentially Affect Proliferation and Intracellular Calcium Signalling in MCF-7 Human Breast Cancer Cells

The assessment of human cancer cell proliferation is a common approach in identifying plant extracts that have potential bioactive effects. In this study, we tested the hypothesis that methanolic extracts of peel and flesh from three archetypal mango cultivars, Irwin (IW), Nam Doc Mai (NDM), and Kensington Pride (KP), differentially affect proliferation, extracellular signal-regulated kinase (ERK) activity, and intracellular calcium () signalling in MCF-7 human breast cancer cells. Mango flesh extracts from all three cultivars did not inhibit cell growth, and of the peel extracts only NDM reduced MCF-7 cell proliferation. Mango cultivar peel and flesh extracts did not significantly change ERK phosphorylation compared to controls; however, some reduced relative maximal peak after adenosine triphosphate stimulation, with NDM peel extract having the greatest effect among the treatments. Our results identify mango interfruit and intrafruit (peel and flesh) extract variability in antiproliferative effects and signalling in MCF-7 breast cancer cells and highlight that parts of the fruit (such as peel and flesh) and cultivar differences are important factors to consider when assessing potential chemopreventive bioactive compounds in plants extracts.

Oral health impacts of medications used to treat mental illness

BACKGROUND Many psychotropic medications affect oral health. This review identified oral side effects for antidepressant, antipsychotic, anticonvulsant, antianxiety and sedative drugs that are recommended in Australia for the management of common mental illnesses and provides recommendations to manage these side-effects. METHODS The Australian Therapeutic Guidelines and the Australian Medicines Handbook were searched for medications used to treat common mental health conditions. For each medication, the generic name, class, and drug company reported side-effects were extracted from the online Monthly Index of Medical Specialties (eMIMs) and UpToDate databases. Meylers Side Effect of Drugs Encyclopaedia was used to identify additional oral adverse reactions to these medications. RESULTS Fifty-seven drugs were identified: 23 antidepressants, 22 antipsychotics or mood stabilisers, and 12 anxiolytic or sedative medications. Xerostomia (91%) the most commonly reported side effect among all classes of medications of the 28 identified symptoms. Other commonly reported adverse effects included dysguesia (65%) for antidepressants, and tardive dyskinesia (94%) or increased salivation (78%) for antipsychotic medications. CONCLUSIONS While xerostomia has often been reported as a common adverse effect of psychotropic drugs, this review has identified additional side effects including dysguesia from antidepressants and tardive dyskinesia and increased salivation from antipsychotics. Clinicians should consider oral consequences of psychotropic medication in addition to other side-effects when prescribing. For antidepressants, this would mean choosing duloxetine, agomelatine and any of the serotonin re-uptake inhibitors except sertraline. In the case of antipsychotics and mood stabilisers, atypical agents have less oral side effects than older alternatives.

GLP-1(28-36)amide, the Glucagon-like peptide-1 metabolite: friend, foe, or pharmacological folly?

The glucagon-like peptide-1 (GLP-1) axis has emerged as a major therapeutic target for the treatment of type 2 diabetes. GLP-1 mediates its key insulinotropic effects via a G-protein coupled receptor expressed on β-cells and other pancreatic cell types. The insulinotropic activity of GLP-1 is terminated via enzymatic cleavage by dipeptidyl peptidase-4. Until recently, GLP-1-derived metabolites were generally considered metabolically inactive; however, accumulating evidence indicates some have biological activity that may contribute to the pleiotropic effects of GLP-1 independent of the GLP-1 receptor. Recent reports describing the putative effects of one such metabolite, the GLP-1-derived nonapeptide GLP-1(28-36) amide, are the focus of this review. Administration of the nonapeptide elevates cyclic adenosine monophosphate (cAMP) and activates protein kinase A, β-catenin, and cAMP response-element binding protein in pancreatic β-cells and hepatocytes. In stressed cells, the nonapeptide targets the mitochondria and, via poorly defined mechanisms, helps to maintain mitochondrial membrane potential and cellular adenosine triphosphate levels and to reduce cytotoxicity and apoptosis. In mouse models of diet-induced obesity, treatment with the nonapeptide reduces weight gain and ameliorates associated pathophysiology, including hyperglycemia, hyperinsulinemia, and hepatic steatosis. Nonapeptide administration in a streptozotocin-induced model of type 1 diabetes also improves glucose disposal concomitant with elevated insulin levels and increased β-cell mass and proliferation. Collectively, these results suggest some of the beneficial effects of GLP-1 receptor analogs may be mediated by the nonapeptide. However, the concentrations required to elicit some of these effects are in the micromolar range, leading to reservations about potentially related therapeutic benefits. Moreover, although controversial, concerns have been raised about the potential for incretin-based therapies to promote pancreatitis and pancreatic and thyroid cancers. The effects ascribed to the nonapeptide make it a potential contributor to such outcomes, raising additional questions about its therapeutic suitability. Notwithstanding, the nonapeptide, like other GLP-1 metabolites, appears to be biologically active. Increasing understanding of such noncanonical GLP-1 activities should help to improve future incretin-based therapeutics.

Managing the oral side effects of medications used to treat multiple sclerosis

BACKGROUND Many medications used to manage multiple sclerosis (MS) affect oral health. This review aimed to identify the oral side-effects of the current drugs recommended in Australia to treat MS and make dental practitioners aware of the range of symptoms. METHODS The Australian Therapeutic Guidelines and the Australian Medicines Handbook were searched for medications used to treat MS. For each medication, the generic name, class, route of administration, dosage and drug company reported side-effects were extracted from the online Monthly Index of Medical Specialties (MIMs) database. Meylers Side-effect of Drugs Encyclopaedia was used to identify any additional oral adverse reactions to medications used to treat MS. RESULTS Fourteen drugs were identified for the treatment of MS progression and 13 drugs for the treatment of MS symptoms. For these medications, 18 oral side-effects were documented: xerostomia was the most common, followed by dysgeusia, dysphagia, mouth ulceration and sinusitis. Anticholinergic drugs caused xerostomia while immunosuppressants resulted in more infection-related side-effects. CONCLUSIONS Dental practitioners should be aware of the range of symptoms likely to be reported by this population. Clinicians are encouraged to continue providing dental care for their patients who develop MS and refer complex cases to specialists.

Describing the role of Australian community pharmacists in oral healthcare

To investigate community pharmacists attitudes, beliefs and practices towards oral health in the Australian setting, describe the frequency and nature of consumer enquiries relating to oral health, and gain insight regarding smoking cessation support for people experiencing oral health problems.

Australian community pharmacists’ knowledge of popular herbal/nutrient weight-loss complementary medicines

Herbal/nutrient weight‐loss complementary medicines (WLCMs) are widely available in community pharmacies and are popular with Australian consumers. Pharmacists have an obligation to ensure they provide appropriate advice to consumers about complementary medicines as they do with registered prescription medicines.

A national survey exploring oral healthcare service provision across Australian community pharmacies

Objectives This study investigated pharmacists’ and pharmacy assistants’ current practices and perspectives with regard to oral healthcare provision across Australian community pharmacies. Design Cross-sectional study. A questionnaire for each pharmacist and pharmacy assistant cohort was developed and administered by online or postal means. Pearson’s χ2 test was used to examine relationships between categorical variables. Participants Pharmacists and pharmacy assistants working within 2100 randomly selected Australian community pharmacies. Results The overall response rate was 58.5% (644/1100) for the pharmacist cohort and 28% (280/1000) for the pharmacy assistant cohort. This represents pharmacy staff responses from 803 community pharmacies across Australia (approximately 14.6%, 803/5500 of community pharmacies nationally). Overall, the majority of pharmacists (80.2%; 516/644) and pharmacy assistants (83.6%; 234/280) reported providing oral health advice/consultations to health consumers up to five times each week. More than half of community pharmacists and pharmacy assistants were involved in identifying signs and symptoms for oral health problems; and the majority believed health consumers were receptive to receiving oral health advice. Additionally, more than 80% of pharmacists and 60% of pharmacy assistants viewed extended oral healthcare roles positively and supported integrating them within their workplace; extended roles include provision of prevention, early intervention and referral to oral healthcare services. The most commonly reported barriers to enhance pharmacy staff involvement in oral healthcare within Australian community pharmacies include lack of knowledge, ongoing training and resources to assist practice. Conclusion This study highlights that Australian pharmacists have an important role in oral health and provides evidence supporting the need for growing partnerships/collaborations between pharmacy and dental healthcare professionals and organisations to develop, implement and evaluate evidence-based resources, interventions and services to deliver improved and responsive oral healthcare within Australian communities.