Uma Devi Palanisamy

Monash University (Malaysia) · Jeffrey Cheah School of Medicine and Health Sciences

Ellagitannin-rich food has been implicated to ameliorate cardiovascular risk, particularly blood pressure (BP). This systematic review and meta-analysis investigated the effect of ellagitannin-rich fruit consumption on BP. Five databases were screened and RCTs reporting the effect of ellagitannin-rich fruit consumption on BP and polyphenol content...

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, th...

The therapeutic effects of food rich in ellagitannins have been established to stem from its microbial metabolite, urolithin. Over the past decade, there has been a growing trend in urolithin research pertaining to its pharmacological properties. The purpose of this systematic review is to collate and synthesise all available data on urolithin's th...

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 it...

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 suffe...

Geraniin, an ellagitannin, has ameliorative properties against high-fat diet (HFD)-induced metabolic syndrome. Since geraniin has poor bioavailability, we hypothesised the interaction of this compound with gut microbiota as the main mechanism for improving metabolic aberrations. Male Sprague Dawley rats were divided into normal diet (ND)- and HFD-f...

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 Sou...

Background Cytochrome P450 (CYP) genetic polymorphism 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...

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 dr...

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 conducte...

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 ma...

Myricetin derivatives from Syzygium malaccense leaf extract are known to have numerous therapeutic efficacies but there is no documented evidence corroborating its safety. Therefore, the present work aimed to evaluate the safety profile of myricetin derivative-rich fraction (MD) from S. malaccense leaf extract through single and repetitive oral adm...

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 revie...

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 poo...

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...

Background: Deaf and hard of hearing patients who use sign language face considerable communication barriers while accessing pharmacy services. Low comfort-levels between community pharmacists and Deaf and hard of hearing patients result in poor interactions and increase patient safety risks. Objective: 1) To examine the way community pharmacists i...

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...

Obesity is a disease growing at an alarming rate and numerous preclinical studies have proven the role of polyphenols in managing this disease. This systematic review explores the prebiotic effect of polyphenols in the management of obesity among animals fed on a high-fat diet. A literature search was carried out in PubMed, Scopus, CINAHL, Web of S...

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 pu...

Malaysian national morbidity surveys on diabetic prevalence have shown ethnical variation among prediabetic and diabetic populations. In our attempt to understand this variation, we studied the α-tocopherol, insulin resistance, β-cell function and receptor of advanced glycation end-products (RAGE) levels, as risk factors of type 2 diabetes, among t...

Hypertension is defined as the persistence of elevated blood pressure in the circulation system. The renin-angiotensin-aldosterone system is a major modulator of blood pressure. Among the risk factors of cardiovascular disease, hypertension is the most preventable and treatable, with drugs such as ACE inhibitors. Many ACE inhibitors are known to ha...

Oral tamoxifen used in the prevention and treatment of ductal carcinoma in situ (DCIS) (estrogen-positive) patients has limited acceptance, due to its adverse side effects. The efficacy of tamoxifen is related to its major metabolite, 4-hydroxytamoxifen. Local transdermal therapy of 4-hydroxytamoxifen to the breast might avert the toxicity of oral...

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/...

Objective: Metabolic syndrome (MetS) which is 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. This study aimed to characterise the...

The relative legumain‐targeting efficiency of a Y‐shaped peptide and a linear peptide with the same amino acid sequence was investigated using in vitro experiments and computer simulations. Flow cytometry and fluorescence microscopy of cell types with varying levels of legumain expression (RAW 264.7, 4T1, MCF 10 A, MCF 7 and MDA MB 231) revealed th...

The anti-inflammatory property of ratite oils as well as its ability to act as a penetration enhancer makes it an ideal agent to be used in transdermal formulations. The present study aims to develop an effective transfersomal delivery of 4-hydroxytamoxifen, an anti-cancer drug, using ratite oil as a carrier agent for the treatment of breast cancer...

Chronic hyperglycemia increases oxidative stress, activates inflammatory pathways and reduces nerve growth factor (NGF) among diabetic patients, which contribute to development of diabetic peripheral neuropathy (DPN). Tocotrienol-Rich Vitamin E (Tocovid) possesses potent antioxidant and anti-inflammatory properties which are postulated to target th...

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 in...

Myricetin derivatives (F2) isolated from leaf extract of Syzygium malaccense (Malay apple) which contains myricitrin predominantly, could potentially serve as functional food ingredient based on previous findings. The present study aimed to investigate the protective effects of F2 against hyperglycemia-induced oxidative stress in ARPE-19 (retinal p...

Background Polyphenols have been implicated to have numerous health benefits, and much of these are attributed to the metabolism of phenolic compounds by gut microbiota. The aim of this systematic review was to examine the effects of polyphenol consumption in modulating gut microbiota and anthropometric variables/clinical markers in randomised cont...

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. Me...

Chronic hyperglycemia in type 2 diabetes mellitus increases oxidative stress and inflammation which contributes to long-term diabetic kidney disease. Tocotrienol-rich vitamin E, as Tocovid, has been shown to reduce oxidative stress and inflammation to ameliorate diabetes in rat models and human subjects. In this prospective, multicenter, double-bli...

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 found in Chinese populations, CYP2C19*23, CYP2C19*24 and CYP2C19*25. Met...

One major source of inter-individual variability in drug pharmacokinetics is genetic polymorphism of the cytochrome P450 (CYP) genes. This study aimed to elucidate the enzyme kinetic and molecular basis for altered activity in three major alleles of CYP2D6, namely CYP2D6*2, CYP2D6*10 and CYP2D6*17. The E. coli-expressed allelic variants were examin...

Despite the lack of its toxicity evaluation, traditional herbal products are being widely used for various health indications. Geraniin, an ellagitannin, is a bioactive compound found in many traditional herbal medicines. In spite its numerous health benefits ranging from anti-inflammatory, anti-hyperglycaemic, hepatoprotective, anti-cancer and ant...

There has been a number of studies looking into an alternative mode of therapy for the treament of breast cancer via 4-hydroxytamoxifen (4-OHT) transdermal administration.This systematic review aims to compare the safety and efficacy of a transdermal 4-OHT local therapy and oral tamoxifen (oral-T) on the treatment of ductal carcinoma in situ breast...

There has been a number of studies looking into an alternative mode of therapy for the treament of breast cancer via 4-hydroxytamoxifen (4-OHT) transdermal administration.This systematic review aims to compare the safety and efficacy of a transdermal 4-OHT local therapy and oral tamoxifen (oral-T) on the treatment of ductal carcinoma in situ breast...

Objective: A preliminary study showed that geraniin extracted from Nephelium lappaceum L. at 50 mg/kg caused reduction in blood glucose and insulin resistance. The present study serves to further investigate the effects of geraniin at increasing doses between 3.125 and 100 mg/kg in high-fat diet-treated rats. Methods: Geraniin (95% purity) was e...

Background Dengue continues to be a major international public health concern. Despite that, there is no clinically approved antiviral for treatment of dengue virus (DENV) infections. In this study, geraniin extracted from the rind of Nephelium lappaceum was shown to inhibit the replication of DENV-2 in both in vitro and in vivo experiments. Metho...

This study aimed to express the major human hepatic drug metabolizing cytochrome P450 (CYP), CYP2C9, together with NADPH cytochrome P450 oxidoreductase (OxR) in Escherichia coli and to evaluate its catalytic activities. Co-expression of CYP2C9 and OxR was achieved by means of separate, compatible plasmids with different antibiotic selection markers...

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 repo...

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 DHoH. Patients and methods: A focus group discussion was conducted with 12 community pharmacists. Participants were recruited using snowball...

Ellagitannin’s, found abundantly in berries, pomegranate, walnuts and almonds, have been increasingly investigated for its health benefits. Geraniin (GE) an ellagitannin, found predominantly in herbal plants, as well has been shown to exhibit a number of biological activities. Like many hydrolysable tannins, geraniin is water-soluble and readily un...

Genetic polymorphism of the cytochrome P450 (CYP) genes particularly affects CYP2D6 and CYP2C19 to a functionally relevant extent, and it is therefore crucial to elucidate the enzyme kinetic and molecular basis for altered catalytic activity of these allelic variants. This study explored the expression and function of the reported alleles CYP2D6*2,...

This oral presentation outlined the ameliorative effects of ellagitannin geraniin on diet-induced lipid dysregulation and hepatic steatosis. Based on the hepatic mRNA sequencing analysis, the molecular mechanism of geraniin is linked to the modulation of genes responsible for mitochondrial function, lipid and steroid metabolic processes. The modula...

Geraniin, a hydrolysable polyphenol derived from Nephelium lappaceum L. fruit rind, has been shown to possess significant antioxidant activity in vitro and recently been recognized for its therapeutic potential in metabolic syndrome. This study investigated its antioxidative strength and protective effects on organs in high-fat diet (HFD)-induced r...

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 modul...

Background The rapid rise and spread in dengue cases, together with the unavailability of safe vaccines and effective antiviral drugs, warrant the need to discover and develop novel anti-dengue treatments. In this study the antiviral activity of geraniin, extracted from the rind of Nephelium lappaceum, against dengue virus type-2 (DENV-2) was inves...

IntroductionSeveral 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 wa...

Background There is a need for students involved in service learning units to be aware of their own positions of privilege so as to help them understand the contributing factors in systems of inequality. Aim To explore pharmacy students’ perceptions of a Privilege Walk Activity ( PWA ) and its impact on their views on social justice. Method A cro...

Porous silicon (PSi) with a suite of most desirable biomaterial properties has attracted great attention as a multifunctional nanoplatform for bioimaging and drug delivery. Various surface functionalization treatments have been reported for PSi to use as an active tumor cell targeting nanovector. In this study, we investigated surface functionaliza...

A novel strain, Streptomyces antioxidans MUSC 164T was recovered from mangrove forest soil located at Tanjung Lumpur, Malaysia. The Gram-positive bacterium forms yellowish-white aerial and brilliant greenish yellow substrate mycelium on ISP 2 agar. A polyphasic approach was used to determine the taxonomy status of strain MUSC 164T. The strain showe...

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...

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...

Geraniin (GE) was identified as the major compound in the rind of Nephelium lappaceum L. (Sapindaceae), while corilagin (CO), ellagic acid (EA) and gallic acid (GA) have been shown to be its main metabolites. GE and its metabolites possess a range of bioactive properties. Lipophilicity of GE, CO, EA and GA was determined and they were established t...

Ratite oils (Emu oil & Ostrich oil), used extensively for centuries by many cultures in the field of cosmetics and pharmaceutical industry, are reputed to have exceptional moisturizing, penetrating and therapeutic qualities in animals and humans. The synergistic effect between the oil (carrier) and the anticancer drug in an ultra-deformable transde...