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Pharmacological mechanisms underlying the vascular activities of Loranthus ferrugineus Roxb. in rat thoracic aorta

Ameer OZ, Salman IM, Siddiqui MJ, Yam MF, Sriramaneni RN, Mohamed AJ, et al.

J Ethnopharmacol, 2010 Jan 8;127(1):19-25.
PMID: 19808083 DOI: 10.1016/j.jep.2009.09.057

The present study was aimed to investigate the pharmacological basis for the use of Loranthus ferrugineus in hypertension.

Matched MeSH terms: In Vitro Techniques
Characterization of the possible mechanisms underlying the hypotensive and spasmogenic effects of Loranthus ferrugineus methanolic extract

Ameer OZ, Salman IM, Siddiqui MJ, Yam MF, Sriramaneni RN, Sadikun A, et al.

Am J Chin Med, 2009;37(5):991-1008.
PMID: 19885958

In the present study, L. ferrugineus methanol extract (LFME) was evaluated for its blood pressure lowering effect in anesthetized normotensive Sprague Dawley (SD) rats and its spasmogenic effect in isolated guinea pig ileum. The possible mechanism(s) of action were also investigated. LFME was obtained by Soxhlet extraction. The rats were fasted overnight and anesthetized with sodium pentobarbitone (60 mg/kg i.p.). LFME was administered in i.v. boluses in the concentrations of 25, 50, 100 and 200 mg/kg respectively, with concomitant monitoring of mean arterial pressure (MAP). It was found that LFME dose-dependently reduced MAP. An i.v. bolus injection of atropine significantly decreased the blood pressure lowering effect of LFME. Similarly, L-NAME (Nomega-nitro-L-arginine methyl ester) significantly lowered both the MAP and the action duration. Conversely, no significant change in MAP was seen following i.v. injections of neostigmine, hexamethonium, prazosin and propranolol. LFME also produced a dose-dependent contractile effect in guinea pig ileum. This contraction was significantly reduced in atropine pre-incubated tissue segments, yet it was significantly enhanced in the presence of neostigmine. No appreciable change in the ability of LFME to contract guinea pig ileum was seen in the presence of hexamethonium. Accordingly, it can be postulated that LFME possesses a marked hypotensive effect that can be attributed to stimulation of muscarinic receptors and/or stimulation of nitric oxide (NO) release. Moreover, LFME retains a considerable spasmogenic action due to its cholinergic properties. The hypotensive and spasmogenic effects of LFME justify its traditional uses.

Matched MeSH terms: In Vitro Techniques
Growth optimization and organogenesis of Gerbera jamesonii Bolus ex. Hook f. in vitro

Hasbullah NA, Taha RM, Awal A

Pak J Biol Sci, 2008 Jun 01;11(11):1449-54.
PMID: 18817245

Regeneration potentials in Gerbera jamesonii Bolus ex. Hook f. from tissues culture system was studied using leaf, petiole and root explants. In vitro regeneration, callus induction and root formation were optimized by manipulation of growth regulators during organogenesis. Various kinds of plant growth regulators such as 6-Benzylaminopurine (BAP), alpha-Naphthalene acetic acid (NAA), 2, 4-Dichlorophenoxyacetic acid (2,4-D), Indole-3-acetic acid (IAA), Indole-3-Butyric acid (IBA), N6-[2-Isopentenyl]adenine (2iP), Kinetin and Zeatin were used to initiate cultures. These plant growth regulators were added to Murashige and Skoog medium in different combinations and concentrations. Adventitious shoots were obtained from petiole explants cultured on Murashige and Skoog (MS) medium supplemented with 2.0 mg L(-1) BAP and 0.5 mg L(-1) NAA. Effectiveness of shoot regeneration medium, type of growth regulator used and duration of induction period were investigated. Leaf explants cultured on MS medium supplemented with 1.0 mg L(-1) BAP and 2.0 mg L(-1) 2, 4-D showed the best results for callus induction. Root explants were found to be non-regenerative in all experiments conducted. Petiole segment was identified as the best explant for regeneration of this species. Regenerated plants were rooted on Murashige and Skoog basal medium. Plantlets were then transferred to field with 75% survival rate.

Matched MeSH terms: In Vitro Techniques
Fulltext α-Amylase and dipeptidyl peptidase-4 (DPP-4) inhibitory effects of Melicope latifolia bark extracts and identification of bioactive constituents using in vitro and in silico approaches

Quek A, Kassim NK, Lim PC, Tan DC, Mohammad Latif MA, Ismail A, et al.

Pharm Biol, 2021 Dec;59(1):964-973.
PMID: 34347568 DOI: 10.1080/13880209.2021.1948065

CONTEXT: Melicope latifolia (DC.) T. G. Hartley (Rutaceae) was reported to contain various phytochemicals including coumarins, flavonoids, and acetophenones.
OBJECTIVE: This study investigates the antidiabetic and antioxidant effects of M. latifolia bark extracts, fractions, and isolated constituents.
MATERIALS AND METHODS: Melicope latifolia extracts (hexane, chloroform, and methanol), fractions, and isolated constituents with varying concentrations (0.078-10 mg/mL) were subjected to in vitro α-amylase and dipeptidyl peptidase-4 (DPP-4) inhibitory assay. Molecular docking was performed to study the binding mechanism of active compounds towards α-amylase and DPP-4 enzymes. The antioxidant activity of M. latifolia fractions and compounds were determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging and β-carotene bleaching assays.
RESULTS: Melicope latifolia chloroform extract showed the highest antidiabetic activity (α-amylase IC50: 1464.32 μg/mL; DPP-4 IC50: 221.58 μg/mL). Fractionation of chloroform extract yielded four major fractions (CF1-CF4) whereby CF3 showed the highest antidiabetic activity (α-amylase IC50: 397.68 μg/mL; DPP-4 IC50: 37.16 μg/mL) and resulted in β-sitosterol (1), halfordin (2), methyl p-coumarate (3), and protocatechuic acid (4). Isolation of compounds 2-4 from the species and their DPP-4 inhibitory were reported for the first time. Compound 2 showed the highest α-amylase (IC50: 197.53 μM) and β-carotene (88.48%) inhibition, and formed the highest number of molecular interactions with critical amino acid residues of α-amylase. The highest DPP-4 inhibition was exhibited by compound 3 (IC50: 911.44 μM).
DISCUSSION AND CONCLUSIONS: The in vitro and in silico analyses indicated the potential of M. latifolia as an alternative source of α-amylase and DPP-4 inhibitors. Further pharmacological studies on the compounds are recommended.

Matched MeSH terms: In Vitro Techniques
Fulltext Empty nano and micro-structured lipid carriers of virgin coconut oil for skin moisturisation

Noor NM, Khan AA, Hasham R, Talib A, Sarmidi MR, Aziz R, et al.

IET Nanobiotechnol, 2016 Aug;10(4):195-9.
PMID: 27463789 DOI: 10.1049/iet-nbt.2015.0041

Virgin coconut oil (VCO) is the finest grade of coconut oil, rich in phenolic content, antioxidant activity and contains medium chain triglycerides (MCTs). In this work formulation, characterisation and penetration of VCO-solid lipid particles (VCO-SLP) have been studied. VCO-SLP were prepared using ultrasonication of molten stearic acid and VCO in an aqueous solution. The electron microscopy imaging revealed that VCO-SLP were solid and spherical in shape. Ultrasonication was performed at several power intensities which resulted in particle sizes of VCO-SLP ranged from 0.608 ± 0.002 µm to 44.265 ± 1.870 µm. The particle size was directly proportional to the applied power intensity of ultrasonication. The zeta potential values of the particles were from -43.2 ± 0.28 mV to -47.5 ± 0.42 mV showing good stability. The cumulative permeation for the smallest sized VCO-SLP (0.608 µm) was 3.83 ± 0.01 µg/cm(2) whereas for larger carriers it was reduced (3.59 ± 0.02 µg/cm(2)). It is concluded that SLP have the potential to be exploited as a micro/nano scale cosmeceutical carrying vehicle for improved dermal delivery of VCO.

Matched MeSH terms: In Vitro Techniques
Effect of limonene on permeation enhancement of ketoprofen in palm oil esters nanoemulsion

Sakeena MH, Elrashid SM, Muthanna FA, Ghassan ZA, Kanakal MM, Laila L, et al.

J Oleo Sci, 2010;59(7):395-400.
PMID: 20513974

This study sets out to investigate the in vitro permeation of ketoprofen from the formulated nanoemulsions through excised rat skin. In vitro permeation of ketoprofen nanoemulsion through rat skin was evaluated in Franz diffusion cells and compared with marketed product (Fastum gel). Limonene which has been reported to be a good enhancer for ketoprofen was selected. Moreover the effects of limonene which was added to the nanoemulsion formulations at levels of 1%, 2%, 3% and on rat skin permeation of ketoprofen were also evaluated. The selected optimized formulation was further studied for skin irritation. Utilization of limonene as a penetration enhancer increased the permeation of ketoprofen from the formulated nanoemulsion with increasing concentrations of limonene. The results obtained showed that nanoemulsion with 3% limonene produced similar and comparable skin permeation of ketoprofen with marketed formulation and the skin irritation study on rats showed the optimized formulation prepared was safe.

Matched MeSH terms: In Vitro Techniques
The effects of propranolol on skeletal muscle contraction, lipid peroxidation products and antioxidant activity in experimental hyperthyroidism

Zaiton Z, Merican Z, Khalid BA, Mohamed JB, Baharom S

Gen. Pharmacol., 1993 Jan;24(1):195-9.
PMID: 8482496

1. The mean levels of lipid peroxidation products, namely conjugated diene and malonaldehyde, were increased in the soleus muscles of hyperthyroid cats, while the mean glutathione peroxidase activity was decreased. No corresponding similar changes were noted in the fast extensor digitorum longus muscles and serum. 2. Propranolol administration prevented the increase in conjugated diene level in the soleus muscles of hyperthyroid cat but not the malonaldehyde level. It also prevented the reduction in glutathione peroxidase activity in the slow oxidative soleus muscles of hyperthyroid cats. 3. Maximal twitch tension, subtetanic tension and maximum tetanic tension of soleus and EDL muscles were reduced in hyperthyroid cats. Propranolol administration for 5 weeks to hyperthyroid cats did not prevent the reduction in tension of contractions of these muscles. 4. It is suggested that lipid peroxidation might not be responsible for the myopathy in hyperthyroidism and propranolol administration does not improve skeletal muscle function in hyperthyroid animals.

Matched MeSH terms: In Vitro Techniques
Fulltext Autophagic cell death is induced by acetone and ethyl acetate extracts from Eupatorium odoratum in vitro: effects on MCF-7 and vero cell lines

Harun FB, Syed Sahil Jamalullail SM, Yin KB, Othman Z, Tilwari A, Balaram P

ScientificWorldJournal, 2012;2012:439479.
PMID: 22666123 DOI: 10.1100/2012/439479

Eupatorium odoratum (EO) contains many biologically active compounds, the anticancer effects of which are not well documented. This study evaluates the cytotoxic effects and mechanism of action of EO extracts on MCF-7 and Vero cell lines. Evaluation of the cytotoxic activity using MTT assay, morphological alterations, and apoptosis were carried out. Autophagy was evaluated by LC3-A protein expression. Cytotoxic activity, membrane blebbing and ballooning at 24 hours, replacement by mass vacuolation, and double membrane vesicles mimicking autophagy and cell death were observed in the cancer cells. No apoptosis was observed by DNA fragmentation assay. Overexpression of LC3-A protein indicated autophagic cell death. Cell cycle analysis showed G0 and G2/M arrest. The Vero cells did not show significant cell death at concentrations <100 μg/mL. These results thus suggest that acetone and ethyl acetate extracts of EO induce cell death through induction of autophagy and hold potential for development as potential anticancer drugs.

Matched MeSH terms: In Vitro Techniques
Studies on Hepatojarakus malayae Yeh, 1955 (Trichostrongylidae: Nematoda)

Balasingam E

Med J Malaya, 1965 Sep;20(1):68-9.
PMID: 4221427
Matched MeSH terms: In Vitro Techniques
In vitro methods used for discovering plant derived products as wound healing agents - An update on the cell types and rationale

Low JS, Mak KK, Zhang S, Pichika MR, Marappan P, Mohandas K, et al.

Fitoterapia, 2021 Oct;154:105026.
PMID: 34480992 DOI: 10.1016/j.fitote.2021.105026

Wounds still pose a huge burden on human health and healthcare systems in many parts of the world. Phytomedicines are being used to heal the wounds since ancient times. Now-a-days also many researchers are exploring the wound healing activity of phytomedicines. Wound healing is a complex process thus, it is always a question mark regarding the best test model (in vivo, ex vivo and in vitro) model to assess the wound healing activity of phytomedicines. In general, the researchers would opt for in vivo model - probably because of closer physiological relevance to human wounds. However, in vivo experimental models are not suitable for high throughput screening and not ethical in terms of initial screening of the phytomedicines. The in vivo models are associated with difficulties in obtaining the ethical approvals, requires huge budget, and resources. We argue that judicious selection of cell types would serve the purpose of developing a physiologically relevant in vitro experimental model. A lot of progress has been made in molecular biology techniques to bridge the gap between in vitro models and their physiological relevance. The in vitro models are the best suited for high throughput screening and to elucidate the molecular mechanisms. The main aim of this review is to provide insights on selection of the cell types for developing physiologically relevant in vitro wound healing assays, which can be used to improve the value of phytomedicines further.

Matched MeSH terms: In Vitro Techniques
Fulltext Stability of the antimalarial drug dihydroartemisinin under physiologically relevant conditions: implications for clinical treatment and pharmacokinetic and in vitro assays

Parapini S, Olliaro P, Navaratnam V, Taramelli D, Basilico N

Antimicrob Agents Chemother, 2015 Jul;59(7):4046-52.
PMID: 25918150 DOI: 10.1128/AAC.00183-15

Artemisinins are peroxidic antimalarial drugs known to be very potent but highly chemically unstable; they degrade in the presence of ferrous iron, Fe(II)-heme, or biological reductants. Less documented is how this translates into chemical stability and antimalarial activity across a range of conditions applying to in vitro testing and clinical situations. Dihydroartemisinin (DHA) is studied here because it is an antimalarial drug on its own and the main metabolite of other artemisinins. The behaviors of DHA in phosphate-buffered saline, plasma, or erythrocyte lysate at different temperatures and pH ranges were examined. The antimalarial activity of the residual drug was evaluated using the chemosensitivity assay on Plasmodium falciparum, and the extent of decomposition of DHA was established through use of high-performance liquid chromatography with electrochemical detection analysis. The role of the Fe(II)-heme was investigated by blocking its reactivity using carbon monoxide (CO). A significant reduction in the antimalarial activity of DHA was seen after incubation in plasma and to a lesser extent in erythrocyte lysate. Activity was reduced by half after 3 h and almost completely abolished after 24 h. Serum-enriched media also affected DHA activity. Effects were temperature and pH dependent and paralleled the increased rate of decomposition of DHA from pH 7 upwards and in plasma. These results suggest that particular care should be taken in conducting and interpreting in vitro studies, prone as their results are to experimental and drug storage conditions. Disorders such as fever, hemolysis, or acidosis associated with malaria severity may contribute to artemisinin instability and reduce their clinical efficacy.

Matched MeSH terms: In Vitro Techniques
Influence of palm oil or its tocotrienol-rich fraction on the lipid peroxidation potential of rat liver mitochondria and microsomes

Nesaretnam K, Devasagayam TP, Singh BB, Basiron Y

Biochem. Mol. Biol. Int., 1993 May;30(1):159-67.
PMID: 8358328

The effect of palm oil, a widely used vegetable oil, rich in tocotrienols, on peroxidation potential of rat liver was examined. Long-term feeding of rats with palm oil as one of the dietary components significantly reduced the peroxidation potential of hepatic mitochondria and microsomes. As compared to hepatic mitochondria isolated from rats fed control or corn oil-rich diet, those from palm oil-fed group showed significantly less susceptibility to peroxidation induced by ascorbate and NADPH. However, in microsomes, only NADPH-induced lipid peroxidation was significantly reduced in rats fed palm oil rich-diet. Though the accumulation of thiobarbituric acid reactive substances during ascorbate-induced lipid peroxidation in mitochondria from rats fed corn oil-rich diet supplemented with tocotrienol-rich fraction (TRF) of palm oil was similar to that of control rats, the initial rate of peroxidation was much slower than those from control or corn oil fed diets. Our in vitro studies as well as analyses of co-factors related to peroxidation potential indicated that the observed decrease in palm oil-fed rats may be due to increased amount of antioxidants in terms of tocotrienol as well as decrease in the availability of substrates for peroxidation.

Matched MeSH terms: In Vitro Techniques
Fulltext Modification of palm kernel oil esters nanoemulsions with hydrocolloid gum for enhanced topical delivery of ibuprofen

Salim N, Basri M, Rahman MB, Abdullah DK, Basri H

Int J Nanomedicine, 2012;7:4739-47.
PMID: 22973096 DOI: 10.2147/IJN.S34700

During recent years, there has been growing interest in the use of nanoemulsion as a drug-carrier system for topical delivery. A nanoemulsion is a transparent mixture of oil, surfactant and water with a very low viscosity, usually the product of its high water content. The present study investigated the modification of nanoemulsions with different hydrocolloid gums, to enhanced drug delivery of ibuprofen. The in vitro characterization of the initial and modified nanoemulsions was also studied.

Matched MeSH terms: In Vitro Techniques
Maduramycosis in a Chinese in West Malaysia

Kutty MK, Bau K

Med J Malaya, 1969 Dec;24(2):151-3.
PMID: 4244142
Matched MeSH terms: In Vitro Techniques
The etiology and pathology of eosinophilic lung (tropical eosinophilia)

Danaraj TJ, Pacheco G, Shanmugaratnam K, Beaver PC

Am J Trop Med Hyg, 1966 Mar;15.(2):183-9.
PMID: 5910525

The finding of microfilariae in lung tissue from patients with eosinophilic lung is reported and the histopathological appearances are described.

Matched MeSH terms: In Vitro Techniques
Aflatoxins in unrefined groundnut oil

Chong YH, Beng CG

Med J Malaya, 1965 Sep;20(1):49-50.
PMID: 4221413
Matched MeSH terms: In Vitro Techniques
Acetate and glucose utilisation and lipid synthesis by cold-acclimated and hypothermic rat-brain homogenates

Perumal R, Bhattathiry EP

Med J Malaya, 1970 Mar;24(3):208-11.
PMID: 4246803
Matched MeSH terms: In Vitro Techniques
A note concerning the possibility that the lesions in scurvy are due to a failure to produce 'compact' collagen fibres

Candlish J

Med J Malaya, 1966 Dec;21(2):161-3.
PMID: 4227387
Matched MeSH terms: In Vitro Techniques
Evaluation of human embryonic stem cells and their differentiated fibroblastic progenies as cellular models for in vitro genotoxicity screening

Vinoth KJ, Manikandan J, Sethu S, Balakrishnan L, Heng A, Lu K, et al.

J Biotechnol, 2014 Aug 20;184:154-68.
PMID: 24862194 DOI: 10.1016/j.jbiotec.2014.05.009

This study evaluated human embryonic stem cells (hESC) and their differentiated fibroblastic progenies as cellular models for genotoxicity screening. The DNA damage response of hESCs and their differentiated fibroblastic progenies were compared to a fibroblastic cell line (HEPM, CRL1486) and primary cultures of peripheral blood lymphocytes (PBL), upon exposure to Mitomycin C, gamma irradiation and H2O2. It was demonstrated that hESC-derived fibroblastic progenies (H1F) displayed significantly higher chromosomal aberrations, micronuclei formation and double strand break (DSB) formation, as compared to undifferentiated hESC upon exposure to genotoxic stress. Nevertheless, H1F cell types displayed comparable sensitivities to genotoxic challenge as HEPM and PBL, both of which are representative of somatic cell types commonly used for genotoxicity screening. Subsequently, transcriptomic and pathways analysis identified differential expression of critical genes involved in cell death and DNA damage response upon exposure to gamma irradiation. The results thus demonstrate that hESC-derived fibroblastic progenies are as sensitive as commonly-used somatic cell types for genotoxicity screening. Moreover, hESCs have additional advantages, such as their genetic normality compared to immortalized cell lines, as well as their amenability to scale-up for producing large, standardized quantities of cells for genotoxicity screening on an industrial scale, something which can never be achieved with primary cell cultures.

Matched MeSH terms: In Vitro Techniques*
High-titred neutralizing antibodies to human enterovirus 71 preferentially bind to the N-terminal portion of the capsid protein VP1

Tan CS, Cardosa MJ

Arch Virol, 2007;152(6):1069-73.
PMID: 17318736

Human enterovirus 71 has emerged as an important pathogen of children in the Asia Pacific region, and it may be important to consider the development of a vaccine against this virus. Human cord serum was used as a source of neutralizing antibodies to determine whether the N- or C-terminal half of the VP1 capsid protein was more likely to harbour neutralizing determinants. Cord sera from 205 individuals were tested for neutralizing antibodies against human enterovirus 71 in an indirect ELISA against recombinant VP1 antigen as well as the N- and C-terminal portions of VP1 antigen. High-titred human neutralizing antibodies were significantly more reactive with the N-terminal half of VP1 than weak or negative sera. The N-terminal half of human enterovirus 71 is likely to have important neutralizing antibody determinants and should be investigated further in vaccine development efforts.

Matched MeSH terms: In Vitro Techniques

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