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Safety assessment of standardized aqueous Brucea javanica extract in rats

Man F, Choo CY

J Ethnopharmacol, 2018 Apr 06;215:21-26.
PMID: 29288829 DOI: 10.1016/j.jep.2017.12.040

ETHNOPHARMACOLOGICAL RELEVANCE: The seeds of Brucea javanica and its aqueous decoction is a traditional medicine consumed by diabetic patients in Malaysia. The daily consumption of B. javanica seeds and it's aqueous decoction causes much concern as the quassinoids and its glycosides from the seeds exhibited various pharmacological activity at low doses.
AIMS OF STUDY: The aim of the present study is to evaluate the repeated dose toxicity of the standardized aqueous extract administered daily for 30 days through oral administration at its effective hypoglycemia doses.
MATERIALS AND METHODS: The seeds were dried, ground and extracted in deionized water. A HPLC-photodiode array method was developed and validated for the standardization of both the hypoglycemia agents, namely bruceine D and E in aqueous extract. Both normoglycemia and streptozotocin (STZ)-induced diabetic rats were fed orally with 15, 30 and 60mg/kg body weight of standardized aqueous extract. The blood glucose was measured at 0-8h. In repeated dose toxicity, similar doses were administered orally to rats for 30 days. At the end of 30 days, the blood was withdrawn and subjected to biochemical and haematology analysis while organs were harvested for histology analysis.
RESULTS: Oral administration of standardized aqueous extract exhibited a dose-response relationship in both the normoglycemia and STZ-induced diabetic rats. Daily oral administration of 15, 30 and 60mg/kg standardized aqueous extract for 30 days to rats did not show signs to toxicity in its biochemical, haematology and histology analysis.
CONCLUSION: In conclusion, although the seeds were reported to contain compounds with various pharmacological activity, the daily oral administration to rats for 30 days do not showed signs of toxicity at its effective hypoglycemia doses.
HPLC-MS/MS method for bioavailability study of bruceines D & E in rat plasma

Man F, Choo CY

J Chromatogr B Analyt Technol Biomed Life Sci, 2017 Sep 15;1063:183-188.
PMID: 28869873 DOI: 10.1016/j.jchromb.2017.08.037

Bruceines D and E are quassinoids from seeds of Brucea javanica (L.) Merr. exhibiting hypoglycemia effect. The crude drug is used as a traditional medicine by diabetes patients. The aim of this study is to understand the bioavailability and pharmacokinetics of both the bruceines D & E. A rapid and sensitive HPLC-MS/MS method was developed and validated for the quantification of both quassinoids, bruceines D & E in rat plasma. Both the bruceines D & E were separated with the Zorbax SBC-18 column with gradient elution and mobile phase system of acetonitrile and deionized water with 0.1% formic acid at a flow rate of 0.5mL/min. Analytes were detected in multiple reaction monitoring (MRM) mode with electrospray positive ionization. The quassinoids, namely bruceines D & E were detected with transitions of m/z 411.2→393.2 and m/z 395.2→377.2, respectively. Another quassinoid, eurycomanone was used as the internal standard with transition of m/z 409.2→391.2. The method was validated and conformed to the regulatory requirements. The validated method was applied to pharmacokinetic and bioavailability studies in rats. The pharmacokinetic study indicated both bruceine D and E were rapidly absorbed into the circulation system and reached its peak concentration at 0.54±0.34h and 0.66±0.30h, respectively. Bruceine E was eliminated slower than Bruceine D with t1/2 value almost increased two-fold compared to Bruceine D. In conclusion, a rapid, selective and sensitive HPLC-MS/MS method was developed for the simultaneous determination of both the bruceines D and E in rat plasma. Both bruceines D and E displayed poor oral bioavailability.
Fulltext Traumatic floating clavicle: a case report

Choo C, Wong H, Nordin A

Malays Orthop J, 2012 Nov;6(3):57-9.
PMID: 25279061 MyJurnal DOI: 10.5704/MOJ.1207.008

Shoulder girdle injuries after high energy traumatic impacts to the shoulder have been well documented. Based on the series of 1603 injuries of the shoulder girdle reported by Cave and colleagues, 85% of the dislocations were glenohumeral, 12% acromioclavicular and 3% sternoclavicular (1). Less frequently described are injuries involving both the sternoclavicular and acromioclavicular joints simultaneously in one extremity. The present report discusses a case of traumatic floating clavicle associated with ipsilateral forearm and wrist injury which was treated surgically.
Posterolateral tibial plateau bone bruises in anterior cruciate ligament (ACL) injuries and its association with lateral meniscal injuries

Rajesh R, Moganadass M, Choo CY

Med J Malaysia, 2023 Nov;78(6):815-820.
PMID: 38031226

INTRODUCTION: This study examined the prevalence of posterolateral tibial bone bruising in isolated anterior cruciate ligament (ACL) injuries, prevalence of meniscal injuries in ACL injuries, as well as the association between posterolateral tibial bone bruising and lateral meniscal tears among those with ACL injury undergoing Primary ACL Reconstruction.
MATERIALS AND METHODS: Retrospective data on 130 patients who underwent primary ACL reconstructions was analysed. Their preoperative magnetic resonance images (MRI) were reviewed for the presence of posterolateral tibial bone bruise. The presence of meniscal injuries was recorded based on the arthroscopic findings from the operative records.
RESULTS: 95 patients were recruited into the study. The prevalence of posterolateral bone bruise in this study was 41%. There was a statistically significant difference when comparing the prevalence of bone bruising to the time of injury to MRI (p<0.001). The prevalence of an injury to at least one meniscus at the time of ACLR surgery was 83.2%. The prevalence of lateral meniscus injuries in patients with bone bruise was found to be 53.9%. The crude odds ratio of a patient having a lateral meniscal tear in the presence of bone bruising was 1.56 (0.68, 3.54). This figure was even higher when it was adjusted for time to MRI and was 2.06 (0.77, 5.46).
CONCLUSION: Prevalence of posterolateral tibial bone bruising in our study was 41%, and the prevalence of meniscal injury to either meniscus at the point of surgery was 83.2%, out of which the lateral meniscus tears were identified during ACLR surgery in 47.3% of the patients. We found there was no association between posterolateral tibial bone bruising to sex, age and mode of injury, but was sensitive to the interval between time of injury and MRI. The overall prevalence of lateral meniscal tears was higher in patients with posterolateral bone bruising but was not statistically significant with a P value of 0.31; however, the Crude odd ratio was 1.56 (0.68, 3.54) and was higher when adjusted to time of injury to MRI 2.06 (0.77, 5.46). We suggest for MRI to be done as soon as possible after injury in regard to bone bruising identification. We should be vigilant to look for lateral meniscal tears and anticipate for its repair in ACL injuries, especially so when we identify posterolateral tibial bruising on the preoperative MRI.
Evaluation of hypoglycemic activity and toxicity profiles of the leaves of Ficus deltoidea in rodents

Ilyanie Y, Wong TW, Choo CY

J Complement Integr Med, 2011 Jan;8.
PMID: 22754938 DOI: 10.2202/1553-3840.1469

Ficus deltoidea Jack (Moraceae) leaf extract is used as an antidiabetic in traditional medicine. Its widespread usage is reflected by the available preparations in the present commercial market. The efficacy of other Ficus species has not been entirely satisfactory and many antidiabetic herbs have demonstrated poor safety profiles. This study examined hypoglycemic and toxicity profiles of F. deltoidea leaf extract in rodent models. Extracts of dried powdered leaves were obtained using methanol solution, n-hexane, chloroform, and n-butanol. These extracts were orally administered to rodents. Their blood glucose and insulin levels, acute and subchronic toxicity, biochemical and histological profiles of liver and kidney were determined. Methanol extract exhibited blood glucose lowering activity in mildly insulin resistant diabetic rats as well as in normoglycemic mice unlike hydrophilic butanol subextract which only expressed its activity in normoglycemic mice. Methanol extract could contain both insulin receptor sensitization and secretagogue constituents. Different from toxic chloroform and hexane subextracts, hydrophilic methanol extract gave zero percent mortality up to 6400 mg/kg in 14 days. It did not induce liver and kidney toxicity upon four-week consumption at 200 mg/kg. The methanol extract possessed mixed antidiabetic actions and exhibited a low level of oral toxicity.
Hypoglycemic effect of quassinoids from Brucea javanica (L.) Merr (Simaroubaceae) seeds

NoorShahida A, Wong TW, Choo CY

J Ethnopharmacol, 2009 Jul 30;124(3):586-91.
PMID: 19439174 DOI: 10.1016/j.jep.2009.04.058

The seeds of Brucea javanica (L.) Merr (Simaroubaceae) are recommended by traditional practitioners for the treatment of diabetes mellitus.
Cytotoxic activity of Typhonium flagelliforme (Araceae)

Choo CY, Chan KL, Takeya K, Itokawa H

Phytother Res, 2001 May;15(3):260-2.
PMID: 11351365

The plant Typhonium flagelliforme (Araceae), commonly known as the 'rodent tuber', is often included as an essential ingredient in various herbal remedies recommended for cancer therapies in Malaysia. Various extracts prepared from either the roots, tubers, stems or leaves were tested for cytotoxic activity on murine P388 leukaemia cells using the MTT assay method. Both the chloroform (IC50 = 6.0 microg/mL) and hexane (IC50 = 15.0 microg/mL) extract from the 'roots and tubers' exhibited weak cytotoxic activity. The hexane extract (IC50 = 65.0 microg/mL) from the 'stems and leaves' exhibited weaker cytotoxic activity than the chloroform extract (IC50 = 8.0 microg/mL). Although the juice extract from the 'roots and tubers' is frequently consumed for cancer treatment, it exhibited poor cytotoxic activity. Further analysis using an amino acid analyser revealed that the juice extract contained a high concentration of arginine (0.874%). A high tryptophan content (0.800%) was confirmed by NMR and HPLC analysis.
High performance liquid chromatography in phytochemical analysis of Eurycoma longifolia

Chan KL, Choo CY, Morita H, Itokawa H

Planta Med, 1998 Dec;64(8):741-5.
PMID: 17253320 DOI: 10.1055/s-2006-957570

An analytical method using HPLC with UV detection was developed to investigate the quassinoid content of Eurycoma longifolia Jack (Simaroubaceae) collected from various sources. Eurycomanone (1), longilactone (2), 14,15beta-dihydroxyklaineanone (3), 15beta-acetyl-14-hydroxyklaineanone (4), 6alpha-hydroxyeurycomalactone (5), and eurycomalactone (7) were isolated as reference standards and together with the synthesized 1beta,12alpha,15beta-triacetyleurycomanone (6, internal standard), were identified by NMR, MS, UV and IR spectroscopies. Their coefficient of variation values for 0.50-35 microg ml(-1) concentrations of quassinoids and their retention times measured within- and between-day were small. The recoveries of the spiked quassinoids in E. longifolia samples and their detection limits at 8.5 times signal to noise ratio were 99.75-109.13% and 0.01 microg ml(-1), respectively. From the root samples analysed, 1 had the highest concentration, being about 16.8-39.6 fold higher than the other quassinoids 2, 3, 5, 7 but 145.3 fold higher than 4 which showed the lowest concentration.
Semisynthetic 15-O-acyl- and 1,15-di-O-acyleurycomanones from Eurycoma longifolia as potential antimalarials

Chan KL, Choo CY, Abdullah NR

Planta Med, 2005 Oct;71(10):967-9.
PMID: 16254833 DOI: 10.1055/s-2005-864188

Among the quassinoids isolated from Eurycoma longifolia Jack, eurycomanone was identified as the most potent and toxic inhibitor of the chloroquine-resistant Gombak A isolate of Plasmodium falciparum. Several diacylated derivatives of eurycomanone, 1,15-di-O-isovaleryleurycomanone, 1,15-di-O-(3,3-dimethylacryloyl)- eurycomanone and 1,15-di-O-benzoyleurycomanone were synthesized by direct acylation with the respective acid chlorides. The monoacylated 15-O-isovaleryleurycomanone was synthesized by selective protection of the other hydroxy groups of eurycomanone with trimethylsilyl trifluoromethanesulphonate to enable the exclusive acylation of its C-15 hydroxy group. This was followed by the removal of the protecting groups with citric acid. The diacylated eurycomanones exhibited lower antiplasmodial activity against the Gombak A isolates and lower toxicity in the brine shrimp assay when compared to eurycomanone. In contrast, the monoacylated derivative displayed comparable antiplasmodial potency to eurycomanone, but its toxicity was reduced. Thus, preliminary studies of the synthesized acylated eurycomanones have shown that acylation only at the C-15 hydroxy group may be worthy of further antimalarial investigation.
Vitexin and isovitexin from the Leaves of Ficus deltoidea with in-vivo α-glucosidase inhibition

Choo CY, Sulong NY, Man F, Wong TW

J Ethnopharmacol, 2012 Aug 1;142(3):776-81.
PMID: 22683902 DOI: 10.1016/j.jep.2012.05.062

The leaves of Ficus deltoidea are used as a traditional medicine by diabetes patients in Malaysia.
The cytotoxicity and chemical constituents of the hexane fraction of Typhonium flagelliforme (Araceace)

Choo CY, Chan KL, Sam TW, Hitotsuyanagi Y, Takeya K

J Ethnopharmacol, 2001 Sep;77(1):129-31.
PMID: 11483390

The plant, Typhonium flagelliforme (Araceae), commonly known as the "rodent tuber" in Malaysia, is often used as an essential ingredient of herbal remedies for alternative cancer therapies. The hexane extract of this plant was evaluated for cytotoxic activity against in vitro culture on P388 murine leukaemia cells and showed weak IC(50) of 15 microg/ml. The partial chemical constituents were identified as methyl esters of hexadecanoic acid, octadecanoic acid, 9-octadecenoic acid and 9,12-octadecadienoic acid. In addition, several common aliphatics were identified as dodecane, tridecane, tetradecane, pentadecane, hexadecane, heptadecane, octadecane, nonadecane and eicosane. The unique methyl ester of 13-phenyltridecanoic acid was isolated and positively identified using spectroscopic methods. None of the identified compounds showed or are known to have cytotoxic behaviour.
Estrogenic phytochemical from Labisia pumila (Myrsinaceae) with selectivity towards estrogen receptor alpha and beta subtypes

Muhamad M, Choo CY, Hasuda T, Hitotsuyanagi Y

Fitoterapia, 2019 Sep;137:104256.
PMID: 31295513 DOI: 10.1016/j.fitote.2019.104256

Labisia pumila var. alata (Myrsinaceae) or "Kacip fatimah" is a famous Malay traditional herb used for the maintenance of women's health. The extracts of L.pumila displayed estrogenic activity in rats. Nonetheless, the estrogenic bioactives were not identified. The aim of the study is to identify estrogenic compounds contributing to the established estrogenic activity. Bioactivity-guided-isolation method guided the isolation of pure bioactives. The hexane extract was subjected to a series of silica gel flash and open column chromatography with increasing amount of ethyl acetate in hexane or methanol in chloroform. Each fraction or pure compounds were evaluated on it's estrogen receptor (ER) binding activity with the fluorescence polarization competitive ERα and ERβ binding assay kit. Cytotoxic assay using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay method was used to establish the cytotoxic activity of the compounds. Four alkyl resorcinols and a dimeric 1,4-benzoquinone, namely belamcandol B (1), 5-pentadec-10'-(Z)-enyl resorcinol (2), 1,3-dihydroxy-5-pentadecylbenzene (3), 5-(heptadec-12'-(Z)-enyl) resorcinol (4) and demethylbelamcandaquinone B (5) were identified with selective binding affinities towards either ERα or ERβ exhibiting selectivity ratio from 0.15-11.9. Alkyl resorcinols (2)-(4) exhibited cytotoxic activity towards HL60 cells with IC50 values from 19.5-22.0 μM. Structural differences between compounds influence the binding affinities to ER subtypes. Further study is needed to establish the agonist or antagonist effect of these compounds on various tissues and to identify if these compounds exert cytotoxic activity through the ERs. When consuming L.pumila as a complementary medicine, careful consideration regarding it's estrogenic compound content should be given due consideration.
Design of oral intestinal-specific alginate-vitexin nanoparticulate system to modulate blood glucose level of diabetic rats

Shaedi N, Naharudin I, Choo CY, Wong TW

Carbohydr Polym, 2021 Feb 15;254:117312.
PMID: 33357875 DOI: 10.1016/j.carbpol.2020.117312

Vitexin of Ficus deltoidea exhibits intestinal α-glucosidase inhibitory and blood glucose lowering effects. This study designs oral intestinal-specific alginate nanoparticulate system of vitexin. Nanospray-dried alginate, alginate/stearic acid and alginate-C18 conjugate nanoparticles were prepared. Stearic acid was adopted to hydrophobize the matrix and minimize premature vitexin release in stomach, whereas C-18 conjugate as immobilized fatty acid to sustain hydrophobic effect and drug release. Nanoparticles were compacted with polyethylene glycol (PEG 3000, 10,000 and 20,000). The physicochemical, drug release, in vivo blood glucose lowering and intestinal vitexin content of nanoparticles and compact were determined. Hydrophobization of alginate nanoparticles promoted premature vitexin release. Compaction of nanoparticles with PEG minimized vitexin release in the stomach, with stearic acid loaded nanoparticles exhibiting a higher vitexin release in the intestine. The introduction of stearic acid reduced vitexin-alginate interaction, conferred alginate-stearic acid mismatch, and dispersive stearic acid-induced particle breakdown with intestinal vitexin release. Use of PEG 10,000 in compaction brought about PEG-nanoparticles interaction that negated initial vitexin release. The PEG dissolution in intestinal phase subsequently enabled particle breakdown and vitexin release. The PEG compacted nanoparticles exhibited oral intestinal-specific vitexin release, with positive blood glucose lowering and enhanced intestinal vitexin content in vivo.
Antiplasmodial studies of Eurycoma longifolia Jack using the lactate dehydrogenase assay of Plasmodium falciparum

Chan KL, Choo CY, Abdullah NR, Ismail Z

J Ethnopharmacol, 2004 Jun;92(2-3):223-7.
PMID: 15138004 DOI: 10.1016/j.jep.2004.02.025

The roots of Eurycoma longifolia Jack have been used as traditional medicine to treat malaria. A systematic bioactivity-guided fractionation of this plant was conducted involving the determination of the effect of its various extracts and their chemical constituents on the lactate dehydrogenase activity of in vitro chloroquine-resistant Gombak A isolate and chloroquine-sensitive D10 strain of Plasmodium falciparum parasites. Their antiplasmodial activity was also compared with their known in vitro cytotoxicity against KB cells. Four quassinoids, eurycomanone (1), 13,21-dihydroeurycomanone (3), 13 alpha(21)-epoxyeurycomanone (4), eurycomalactone (6) and an alkaloid, 9-methoxycanthin-6-one (7), displayed higher antiplasmodial activity against Gombak A isolate but were less active against the D10 strain when compared with chloroquine. Amongst the compounds tested, 1 and 3 showed higher selectivity indices obtained for the cytotoxicity to antiplasmodial activity ratio than 14,15 beta-dihydroxyklaineanone (2), eurycomanol (5), 6 and 7.
Phytochemical constituents from Cassia alata with inhibition against methicillin-resistant Staphylococcus aureus (MRSA)

Hazni H, Ahmad N, Hitotsuyanagi Y, Takeya K, Choo CY

Planta Med, 2008 Dec;74(15):1802-5.
PMID: 18991205 DOI: 10.1055/s-0028-1088340

The methanolic extract of the leaves of CASSIA ALATA was sequentially partitioned in increasing polarity to afford the hexane, chloroform, butanol and residual extract. Crude extracts were evaluated against MRSA using the agar well diffusion assay. The butanol and chloroform extracts both exhibited inhibition against MRSA with inhibition indexes of 1.03 +/- 0.16 and 0.78 +/- 0.07 at the concentration of 50 mg/mL. The butanol extracts were further purified using silica gel and reverse phase chromatography to afford kaempferol ( 1), kaempferol 3- O-beta-glucopyranoside ( 2), kaempferol 3- O-gentiobioside ( 3) and aloe emodin ( 4). The four constituents showed varying degrees of inhibition against MRSA. Both 1 and 4 exhibited MIC (50) values of 13.0 +/- 1.5 microg/mL and 12.0 +/- 1.5 microg/mL, respectively. The kaempferol glycosides 2 and 3 were less active with MIC (50) values of 83.0 +/- 0.9 microg/mL and 560.0 +/- 1.2 microg/mL, respectively. A free hydroxyl group at C-3 of the flavonol structure is a structural requirement for the inhibition of MRSA.
Fulltext Eurycomanone and eurycomanol from Eurycoma longifolia Jack as regulators of signaling pathways involved in proliferation, cell death and inflammation

Hajjouli S, Chateauvieux S, Teiten MH, Orlikova B, Schumacher M, Dicato M, et al.

Molecules, 2014 Sep 16;19(9):14649-66.
PMID: 25230121 DOI: 10.3390/molecules190914649

Eurycomanone and eurycomanol are two quassinoids from the roots of Eurycoma longifolia Jack. The aim of this study was to assess the bioactivity of these compounds in Jurkat and K562 human leukemia cell models compared to peripheral blood mononuclear cells from healthy donors. Both eurycomanone and eurycomanol inhibited Jurkat and K562 cell viability and proliferation without affecting healthy cells. Interestingly, eurycomanone inhibited NF-κB signaling through inhibition of IκBα phosphorylation and upstream mitogen activated protein kinase (MAPK) signaling, but not eurycomanol. In conclusion, both quassinoids present differential toxicity towards leukemia cells, and the presence of the α,β-unsaturated ketone in eurycomanone could be prerequisite for the NF-κB inhibition.
Fulltext Functional Outcome after Treatment of Aggressive Tumours in the Distal Radius: Comparison between Reconstruction using Proximal Fibular Graft and Wrist Fusion

Choo CY, Mat-Saad AM, Wan-Azman WS, Wan Z, Nor-Azman MZ, Yahaya S, et al.

Malays Orthop J, 2018 Nov;12(3):19-23.
PMID: 30555642 MyJurnal DOI: 10.5704/MOJ.1811.004

Introduction: Restoration of a functional hand is the ultimate goal following a distal radius tumour resection. The early outcomes of mobile wrist reconstruction are satisfactory; however, long-term results are unpredictable due to late wrist instability and degenerative arthritis. Our aim is to compare mobile wrist reconstruction with wrist fusion (pan-carpal fusion) in our cohort of patients. Materials and Methods: A retrospective cohort study was performed for functional outcomes of all patients who underwent resection for distal radius tumour and treated with either fusion or reconstruction of the wrist in a single institution from years 2000-2013 with a minimum of three years follow-up. Results: Eleven patients were included in the study, six of whom had wrist reconstruction with proximal fibula graft and the remaining five wrist fusion, with a mean follow-up of 6.3 years. The mean Musculoskeletal Tumour Society (MSTS) score was 82.78%, ranging from 70% to 93.3%. Average grip strength compared to the normal contralateral hand was 60.0% for total wrist fusion, which was better than wrist reconstruction with 58.07%. There was no difference in the functional outcome between fusion and mobile reconstruction in our study. Osteoarthritis changes and subluxation of the wrist joint were the most common findings in the long-term follow-up for this group. Conclusion: There was no difference in the functional outcome of the long-term follow-up between the two groups.

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