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Validation of Multi-epitope Peptides Encapsulated in PLGA Nanoparticles Against Influenza A Virus

Heng WT, Lim HX, Tan KO, Poh CL

Pharm Res, 2023 Aug;40(8):1999-2025.
PMID: 37344603 DOI: 10.1007/s11095-023-03540-x

BACKGROUND: Influenza is a highly contagious respiratory disease which poses a serious threat to public health globally, causing severe diseases in 3-5 million humans and resulting in 650,000 deaths annually. The current licensed seasonal influenza vaccines lacked cross-reactivity against novel emerging influenza strains as they conferred limited neutralising capabilities. To address the issue, we designed a multi-epitope peptide-based vaccine delivered by the self-adjuvanting PLGA nanoparticles against influenza infections.
METHODS: A total of six conserved peptides representing B- and T-cell epitopes of Influenza A were identified and they were formulated in either incomplete Freund's adjuvant containing CpG ODN 1826 or being encapsulated in PLGA nanoparticles for the evaluation of immunogenicity in BALB/c mice.
RESULTS: The self-adjuvanting PLGA nanoparticles encapsulating the six conserved peptides were capable of eliciting the highest levels of IgG and IFN- γ producing cells. In addition, the immunogenicity of the six peptides encapsulated in PLGA nanoparticles showed greater humoral and cellular mediated immune responses elicited by the mixture of six naked peptides formulated in incomplete Freund's adjuvant containing CpG ODN 1826 in the immunized mice. Peptide 3 from the mixture of six peptides was found to exert necrotic effect on CD3+ T-cells and this finding indicated that peptide 3 should be removed from the nanovaccine formulation.
CONCLUSION: The study demonstrated the self-adjuvanting properties of the PLGA nanoparticles as a delivery system without the need for incorporation of toxic and costly conventional adjuvants in multi-epitope peptide-based vaccines.

Matched MeSH terms: Peptides
Fulltext Angiographic anatomy of the extracranial and intracranial portions of the internal carotid arteries in donkeys

Khairuddin NH, Sullivan M, Pollock PJ

Ir Vet J, 2017 04 20;70:12.
PMID: 28439406 DOI: 10.1186/s13620-017-0090-0

BACKGROUND: In horses, the extracranial and intracranial pathway of the internal carotid artery has been described. The extracranial pathway of the internal carotid artery begins at the carotid termination and runs on the dorsal surface of the medial compartment of the guttural pouch. Thereafter the internal carotid artery passes through the foramen lacerum to continue intracranially, forming part of the rostrolateral quadrants of the cerebral arterial circle (Circle of Willis). The objectives of this study were to define and record the anatomy of the carotid arterial tree and the internal carotid artery in donkeys using angiographic techniques. This is a prospective descriptive study on 26 cadaveric donkeys.
METHODS: Twenty six donkey cadavers of mixed, age, sex and use presented for reasons unrelated to disease of the guttural pouch were subjected to carotid and cerebral angiography using rotational angiography. Rotational angiographic and 3 dimensional multiplanar reconstructive (3D-MPR) findings were verified with an arterial latex casting technique followed by dissection and photography.
RESULTS: The following variations of the carotid arterial tree were identified: [1] the internal carotid and occipital arteries shared a common trunk, [2] the linguofacial trunk originated from the common carotid artery causing the common carotid artery to terminate as four branches, [3] the external carotid artery was reduced in length before giving rise to the linguofacial trunk, mimicking the appearance of the common carotid artery terminating in four branches, [4] the internal carotid artery originated at a more caudal position from the common carotid artery termination.
CONCLUSION: Veterinarians should be aware that considerable variation exists in the carotid arterial tree of donkeys and that this variation may differ markedly from that described in the horse.

Matched MeSH terms: Intracellular Signaling Peptides and Proteins
Preclinical Development of a Novel Epitope-based DNA Vaccine Candidate against SARS-CoV-2 and Evaluation of Immunogenicity in BALB/c Mice

Khalid K, Lim HX, Anwar A, Tan SH, Hwang JS, Ong SK, et al.

AAPS PharmSciTech, 2024 Mar 12;25(3):60.
PMID: 38472523 DOI: 10.1208/s12249-024-02778-x

The protective efficacies of current licensed vaccines against COVID-19 have significantly reduced as a result of SARS-CoV-2 variants of concern (VOCs) which carried multiple mutations in the Spike (S) protein. Considering that these vaccines were developed based on the S protein of the original SARS-CoV-2 Wuhan strain, we designed a recombinant plasmid DNA vaccine based on highly conserved and immunogenic B and T cell epitopes against SARS-CoV-2 Wuhan strain and the Omicron VOC. Literature mining and bioinformatics were used to identify 6 immunogenic peptides from conserved regions of the SARS-CoV-2 S and membrane (M) proteins. Nucleotide sequences encoding these peptides representing highly conserved B and T cell epitopes were cloned into a pVAX1 vector to form the pVAX1/S2-6EHGFP recombinant DNA plasmid vaccine. The DNA vaccine was intranasally or intramuscularly administered to BALB/c mice and evaluations of humoral and cellular immune responses were performed. The intramuscular administration of pVAX1/S2-6EHGFP was associated with a significantly higher percentage of CD8+ T cells expressing IFN-γ when compared with the empty vector and PBS controls. Intramuscular or intranasal administrations of pVAX1/S2-6EHGFP resulted in robust IgG antibody responses. Sera from mice intramuscularly immunized with pVAX1/S2-6EHGFP were found to elicit neutralizing antibodies capable of SARS-CoV-2 Omicron variant with the ACE2 cell surface receptor. This study demonstrated that the DNA vaccine construct encoding highly conserved immunogenic B and T cell epitopes was capable of eliciting potent humoral and cellular immune responses in mice.

Matched MeSH terms: Peptides
Fulltext Enzyme Hydrolysates from Stichopus horrens as a New Source for Angiotensin-Converting Enzyme Inhibitory Peptides

Forghani B, Ebrahimpour A, Bakar J, Abdul Hamid A, Hassan Z, Saari N

Evid Based Complement Alternat Med, 2012;2012:236384.
PMID: 22927875 DOI: 10.1155/2012/236384

Stichopus horrens flesh was explored as a potential source for generating peptides with angiotensin-converting enzyme (ACE) inhibitory capacity using 6 proteases, namely alcalase, flavourzyme, trypsin, papain, bromelain, and protamex. Degree of hydrolysis (DH) and peptide profiling (SDS-PAGE) of Stichopus horrens hydrolysates (SHHs) was also assessed. Alcalase hydrolysate showed the highest DH value (39.8%) followed by flavourzyme hydrolysate (32.7%). Overall, alcalase hydrolysate exhibited the highest ACE inhibitory activity (IC(50) value of 0.41 mg/mL) followed by flavourzyme hydrolysate (IC(50) value of 2.24 mg/mL), trypsin hydrolysate (IC(50) value of 2.28 mg/mL), papain hydrolysate (IC(50) value of 2.48 mg/mL), bromelain hydrolysate (IC(50) value of 4.21 mg/mL), and protamex hydrolysate (IC(50) value of 6.38 mg/mL). The SDS-PAGE results showed that alcalase hydrolysate represented a unique pattern compared to others, which yielded potent ACE inhibitory peptides with molecular weight distribution lower than 20 kDa. The evaluation of the relationship between DH and IC(50) values of alcalase and flavourzyme hydrolysates revealed that the trend between those parameters was related to the type of the protease used. We concluded that the tested SHHs would be used as a potential source of functional ACE inhibitory peptides for physiological benefits.

Matched MeSH terms: Peptides
Fulltext Response Surface Optimisation for the Production of Antioxidant Hydrolysates from Stone Fish Protein Using Bromelain

Auwal SM, Zarei M, Abdul-Hamid A, Saari N

Evid Based Complement Alternat Med, 2017;2017:4765463.
PMID: 29234403 DOI: 10.1155/2017/4765463

Protein hydrolysates produced from different food sources exhibit therapeutic potential and can be used in the management of chronic diseases. This study was targeted to optimise the conditions for the hydrolysis of stone fish protein to produce antioxidant hydrolysates using central composite design (CCD) by response surface methodology (RSM). The stone fish protein was hydrolysed under the optimum predicted conditions defined by pH (6.5), temperature (54°C), E/S ratio (1.5%), and hydrolysis time (360 min). The hydrolysates were then evaluated for 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•) scavenging activity and ferrous ion- (Fe2+-) chelating activity. Results validation showed no significant difference between the experimental values of DPPH• scavenging activity (48.94%) and Fe2+-chelating activity (25.12%) obtained at 54.62% degree of hydrolysis (DH) compared to their corresponding predicted values of 49.79% and 24.08% at 53.08% DH, respectively. The hydrolysates demonstrated non-Newtonian behavior (n < 1) with stronger shear-thinning effect and higher viscosities at increasing concentration. Thus, RSM can be considered as a promising strategy to optimise the production of stone fish protein hydrolysates containing antioxidant peptides. It is hoped that this finding will enhance the potential of stone fish protein hydrolysates (SHs) as therapeutic bioactive ingredient in functional foods development.

Matched MeSH terms: Peptides
Quadrupole-Time-of-Flight Mass Spectrometric Identification of Hemoglobin Subunits α, β, γ and δ in Unknown Peaks of High Performance Liquid Chromatography of Hemoglobin in β-Thalassemias

Abdullah UYH, Ibrahim HM, Mahmud NB, Salleh MZ, Kek TL, Noorizhab MNFB, et al.

Hemoglobin, 2019 May;43(3):182-187.
PMID: 31298599 DOI: 10.1080/03630269.2019.1632893

This is the first report of quadrupole time-of-flight (Q-TOF) mass spectrometric identification of the hemoglobin (Hb) subunits, α, β, δ and γ peptides, derived from enzymatic-digestion of proteins in the early unknown peaks of the cation exchange chromatography of Hb. The objectives were to identify the unknown high performance liquid chromatography (HPLC) peaks in healthy subjects and in patients with β-thalassemia (β-thal). The results demonstrate the existence of pools of free globin chains in red blood cells (RBCs). The α-, β-, δ- and γ-globin peptides were identified in the unknown HPLC peaks. The quantification and role of the free globin pool in patients with β-thal requires further investigation. Identification of all types of Hb subunits in the retention time (RT) before 1 min. suggests that altered Hbs is the nature of these fast-eluting peaks. Relevancy of thalassemias to the protein-aggregation disorders will require review of the role of free globin in the pathology of the disease.

Matched MeSH terms: Peptides
Fulltext 18F[AlF]-radiolabelled Peptides on the Automated Synthesis Platform: Translating the Laboratory Bench Work to Bedside

Hassan H, Razak HRA, Saad FFA, Kumar V

Malays J Med Sci, 2019 Jul;26(4):122-126.
PMID: 31496901 MyJurnal DOI: 10.21315/mjms2019.26.4.14

Using radiolabelled peptides that bind, with high affinity and specificity, to receptors on tumour cells is one of the most promising fields in modern molecular imaging and targeted radionuclide therapy (1). In the emergence of molecular imaging and nuclear medicine diagnosis and therapy, albeit theranostic, radiolabelled peptides have become vital tools for in vivo visualisation and monitoring physiological and biochemical processes on molecular and cellular levels (2). This approach may benefit patients in the era of personalised medicine.

Matched MeSH terms: Peptides
Fulltext Drosophila melanogaster: Deciphering Alzheimer's Disease

Tan FHP, Azzam G

Malays J Med Sci, 2017 Mar;24(2):6-20.
PMID: 28894399 MyJurnal DOI: 10.21315/mjms2017.24.2.2

Alzheimer's disease (AD) is the most widespread neurodegenerative disorder worldwide. Its pathogenesis involves two hallmarks: aggregation of amyloid beta (Aβ) and occurrence of neurofibrillary tangles (NFTs). The mechanism behind the disease is still unknown. This has prompted the use of animal models to mirror the disease. The fruit fly, Drosophila melanogaster has garnered considerable attention as an organism to recapitulate human disorders. With the ability to monopolise a multitude of traditional and novel genetic tools, Drosophila is ideal for studying not only cellular aspects but also physiological and behavioural traits of human neurodegenerative diseases. Here, we discuss the use of the Drosophila model in understanding AD pathology and the insights gained in discovering drug therapies for AD.

Matched MeSH terms: Amyloid beta-Peptides
Neuroprotective effect from stem bark extracts of Knema laurina against H₂O₂- and Aβ(1-42)-induced cell death in human SH-SY5Y cells

Ismail N, Akhtar MN, Ismail M, Zareen S, Shah SA, Lajis NH, et al.

Nat Prod Res, 2015;29(16):1571-4.
PMID: 25471591 DOI: 10.1080/14786419.2014.985676

The stem bark extracts of Knema laurina inhibited the hydrogen peroxide (H2O2)- and aggregated amyloid β-peptide 1-42 length (Aβ(1-42))-induced cell death in differentiated SH-SY5Y cells. Exposure of 250 μM H2O2 or 20 μM Aβ(1-42) to the cells for 24 h reduced 50% of cell viability. Pretreatment of cells with ethyl acetate extract (EAE) or n-butanol extract (BE) at 300 μg/mL and then exposure to H2O2 protected the cells against the neurotoxic effects of H2O2. Besides, methanolic extract (ME) at 1 and 10 μg/mL exerted neuroprotective effect on Aβ(1-42)-induced toxicity to the cells. These results showed that EAE, BE and ME exhibited neuroprotective activities against H2O2- and Aβ(1-42)-induced cell death. Flavonoids (3-6) and β-sitosterol glucoside (8) were isolated from the EAE. Compound 1 was isolated from hexane extract, and compounds 2 and 7 were isolated from dichloromethane extract. All these observations provide the possible evidence for contribution in the neuroprotective effects.

Matched MeSH terms: Amyloid beta-Peptides/adverse effects
Brain endothelial cells increase the proliferation of Plasmodium falciparum through production of soluble factors

Khaw LT, Ball HJ, Mitchell AJ, Grau GE, Stocker R, Golenser J, et al.

Exp Parasitol, 2014 Oct;145:34-41.
PMID: 25045850 DOI: 10.1016/j.exppara.2014.07.002

We here describe the novel finding that brain endothelial cells in vitro can stimulate the growth of Plasmodium falciparum through the production of low molecular weight growth factors. By using a conditioned medium approach, we show that the brain endothelial cells continued to release these factors over time. If this mirrors the in vivo situation, these growth factors potentially would provide an advantage, in terms of enhanced growth, for sequestered parasitised red blood cells in the brain microvasculature. We observed this phenomenon with brain endothelial cells from several sources as well as a second P. falciparum strain. The characteristics of the growth factors included: <3 kDa molecular weight, heat stable, and in part chloroform soluble. Future efforts should be directed at identifying these growth factors, since blocking their production or actions might be of benefit for reducing parasite load and, hence, malaria pathology.

Matched MeSH terms: Intercellular Signaling Peptides and Proteins/metabolism*
Silica exposure is associated with an increased risk of developing ACPA-positive rheumatoid arthritis in an Asian population: evidence from the Malaysian MyEIRA case-control study

Yahya A, Bengtsson C, Larsson P, Too CL, Mustafa AN, Abdullah NA, et al.

Mod Rheumatol, 2014 Mar;24(2):271-4.
PMID: 24593203 DOI: 10.3109/14397595.2013.854076

OBJECTIVES: Silica exposure has been associated with an increased risk of developing rheumatoid arthritis (RA), especially among smokers. In this study, we aimed at examining the association between silica exposure (and its interaction with smoking) and the risk of RA in the Malaysian population.
METHODS: In total, 149 cases and 213 matched controls, all men, were included between August 2005 and December 2009. A case was defined as a person with early diagnosed RA using the 1987 American College of Rheumatology criteria for RA. Controls were randomly selected matched on sex, age and residential area. Silica exposure was defined as exposure to stone dust, rock drilling or stone crushing, and smoking status was categorized as ever/never cigarette smoking.
RESULTS: An increased risk of anti-citrullinated protein antibody (ACPA)-positive RA (OR = 2.4, 95 % CI 1.0-5.6) was observed among those exposed to silica. Ever-smokers exposed to silica had a particularly high risk of developing ACPA-positive RA (OR = 7.5, 95 % CI 2.3-24.2), compared with never-smokers not exposed to silica. No association was found regarding ACPA-negative RA.
CONCLUSION: Our data demonstrate that exposure to both silica and cigarette smoke comprise risks for developing RA in the Malaysian genetic context. The findings expand a link between environmental lung exposures and ACPA-positive RA to Asian populations.

Matched MeSH terms: Peptides, Cyclic/immunology*
Fulltext CD133 marks for colorectal adenocarcinoma

Chew MF, Teoh KH, Cheah PL

Malays J Pathol, 2012 Jun;34(1):25-8.
PMID: 22870594 MyJurnal

CD133, a marker which has been advocated to mark colorectal carcinoma "stem or tumour initiating cells" is amongst the frequently studied markers in colorectal cancer. A study was conducted at the Department of Pathology, University of Malaya Medical Centre to determine the expression of CD133 in 56 archived, formalin-fixed, paraffin-embedded colorectal adenocarcinoma in comparison with adjacent benign colorectal epithelium by immunohistochemical staining for CD133 expression. CD133 immunopositivity was determined as staining at the glandular luminal surface or in the intraluminal debris. Expression was semiquantitated for (1) proportion of CD133 immunopositivity in the malignant or adjacent benign colorectal epithelium and (2) intensity of staining. The final score of CD133 immunopositivity was arbitrarily taken as proportion of CD133 immunopositivity multiplied by intensity of staining in both the malignant and adjacent benign colorectal epithelium. CD133 expression was observed in significantly increased frequency in 49 (87.5%) colorectal adenocarcinoma compared with 15 (26.8%) of the adjacent benign colorectal epithelium (p<0.05). In terms of immunopositivity score (proportion of CD133 immunopositivity multiplied by intensity of staining), colorectal adenocarcinoma had a mean arbitrary score of 8.5 which was significantly higher than the mean immunopositivity score of 0.5 of the adjacent benign colorectal epithelium (p<0.05). In addition, the maximum immunopositivity score for the adjacent benign colorectal epithelium was 4, while 38 (67.9%) of colorectal adenocarcinoma had scores >4. This study shows that CD133 is able to mark colorectal adenocarcinoma but it is still unclear at this juncture whether CD133 is indeed a marker for colorectal adenocarcinoma "stem cells".

Matched MeSH terms: Peptides/metabolism*
Fulltext Ethnic differences in the prognostic utility of rheumatoid factor isotypes and anticyclic citrullinated peptides in rheumatoid arthritis patients: a cross-sectional study

Gomez EL, Gun SC, Somanath SD, Chinna K, Radhakrishnan AK

Mod Rheumatol, 2013 Jul;23(4):716-21.
PMID: 22854883 DOI: 10.1007/s10165-012-0718-6

OBJECTIVES: The prognostic significance of rheumatoid factor (RF) and anticyclic citrullinated peptide antibody (anti-CCP) in rheumatoid arthritis (RA) remains contentious due to the conflicting lines of evidence. This study aims to determine the association between RF isotypes and anti-CCP with disease severity in RA patients from three ethnic groups.
METHODS: A total of 147 RA patients from three different ethnic groups (Malays, Chinese, and Indians) who fulfilled the 1987 American College of Rheumatology (ACR) revised criteria for RA were recruited into this study. The seroprevalence of RF isotypes immunoglobulin (Ig)A, IgG, and IgM, as well as anti-CCP was determined using commercial enzyme-linked immunosorbent assay (ELISA) kits. Multinomial regression analysis was performed to assess the independent effects of autoantibody status on the development of deforming and erosive RA and the presence of extra-articular manifestations (EAM).
RESULTS: In Chinese patients, we found a significant association (p < 0.05) between IgG RF and anti-CCP and the presence of erosive disease, as well as IgM RF and IgG RF with the presence of joint deformities. In Indian patients, IgM RF was associated with deforming disease, whereas none of the antibodies were associated with disease severity in Malay patients. Multinomial regression analysis revealed that IgG RF was the most important predictor variable for erosive disease in Chinese patients, and IgM RF the only predictor variable associated with deforming disease in both Chinese and Indian RA patients.
CONCLUSIONS: There is variability in the phenotypic association of RF isotypes and anti-CCP in relation to disease severity of RA in the three ethnic groups. RF, in particular, IgG and IgM, may be better prognosticators of severe disease in Chinese and Indian patients.

Matched MeSH terms: Peptides, Cyclic/immunology*
Smoking is associated with an increased risk of developing ACPA-positive but not ACPA-negative rheumatoid arthritis in Asian populations: evidence from the Malaysian MyEIRA case-control study

Yahya A, Bengtsson C, Lai TC, Larsson PT, Mustafa AN, Abdullah NA, et al.

Mod Rheumatol, 2012 Aug;22(4):524-31.
PMID: 22006120 DOI: 10.1007/s10165-011-0544-2

We investigated the association between cigarette smoking and the risk of developing rheumatoid arthritis (RA) in the Malaysian population. A total of 1,056 RA patients and 1,416 matched controls aged 18-70 years within a defined area of Peninsular Malaysia were evaluated in a case-control study between August 2005 and December 2009. A case was defined as a person with early diagnosed RA using the 1987 American College of Rheumatology criteria for RA. Controls were randomly selected matched for sex, age, and residential area. Cases and controls answered a questionnaire on a broad range of issues, including lifestyle factors and smoking habits wherein current and former smoking was classified as ever-smoking. The presence of anti-citrullinated peptide antibodies (ACPA) was determined for cases and controls. We found that ever-smokers had an increased risk of developing ACPA-positive RA [odds ratio (OR) = 4.1, 95% confidence interval (CI) 1.9-9.2] but not ACPA-negative RA (OR = 0.7, 95% CI 0.3-2.0), compared with never-smokers. A significant dose-response relationship between cumulative dose of smoking and risk of ACPA-positive RA was observed (<20 pack-years OR = 3.3, 95% CI 1.1-9.8; at least 20 pack-years OR = 5.2, 95% CI 1.6-17.6). Hence, smoking is associated with an increased risk of ACPA-positive RA in the Malaysian population, in which the genetic context is similar to several other Asian countries.

Matched MeSH terms: Peptides, Cyclic/immunology*
Fulltext Analytical and diagnostic performance of an automated anti-CCP assay

Pavai S, Sargunan S, Zain AA, Chow SK

Malays J Pathol, 2011 Dec;33(2):101-6.
PMID: 22299210 MyJurnal

Aim: Autoantibodies against cyclic citrullinated peptide (anti-CCP) are considered to be a sensitive and specific marker for rheumatoid arthritis (RA). This study evaluated the diagnostic and analytical performances of the automated anti-CCP assay.
Materials and Method: Sera from 80 patients with established RA, 65 from other rheumatic diseases (non-RA) and 55 from healthy controls were studied using second generation anti-CCP. Rheumatoid factor (RF) was also assayed in each sample, and the results were compared to the anti-CCP fi ndings. Serum pools were used to determine the precision and linearity.
Results: At a cut-off of 7.4 U/ml for anti-CCP, the sensitivity and specificity for RA were 65% and 98% respectively. RF had a sensitivity of 58% and a lower specifi city of 93 % than anti-CCP. Conclusion: The high specificity of the assay suggests that anti-CCP is useful in the diagnosis of rheumatoid arthritis and in our cohort of study population anti-CCP exhibits a better diagnostic value than RF. A considerable proportion (28%) of RF-negative RA patients were anti-CCP positive. Based on analytical performance of the assay, we conclude that full automation and high throughput features of AxSYM makes it an ideal platform for routine testing of anti-CCP.
Study site: Rheumatology clinic, University Malaya Medical Centre (UMMC), Kuala Lumpur, Malaysia

Matched MeSH terms: Peptides, Cyclic/immunology*
Effects of macrophage colony-stimulating factor on microglial responses to lipopolysaccharide and beta amyloid

Vidyadaran S, Ooi YY, Subramaiam H, Badiei A, Abdullah M, Ramasamy R, et al.

Cell Immunol, 2009;259(1):105-10.
PMID: 19577228 DOI: 10.1016/j.cellimm.2009.06.005

A challenge for studies involving microglia cultures is obtaining sufficient cells for downstream experiments. Macrophage colony-stimulating factor (M-CSF) has been used to improve yield of microglia in culture. However, the effects of M-CSF on activation profiles of microglia cultures are still unclear. Microglia activation is characterised by upregulation of co-stimulatory molecules and an inflammatory phenotype. The aim of this study is to demonstrate whether M-CSF supplementation alters microglial responses in resting and activated conditions. Microglia derived from mixed glia cultures and the BV-2 microglia cell line were cultivated with/without M-CSF and activated with lipopolysaccharide (LPS) and beta amyloid (Abeta). We show M-CSF expands primary microglia without affecting microglial responses to LPS and Abeta, as shown by the comparable expression of MHC class II and CD40 to microglia grown without this growth factor. M-CSF supplementation in BV-2 cells had no effect on nitric oxide (NO) production. Therefore, M-CSF can be considered for improving microglia yield in culture without introducing activation artefacts.

Matched MeSH terms: Amyloid beta-Peptides/pharmacology*
Solubilized antigen of Blastocystis hominis facilitates the growth of human colorectal cancer cells, HCT116

Chandramathi S, Suresh K, Kuppusamy UR

Parasitol Res, 2010 Mar;106(4):941-5.
PMID: 20165878 DOI: 10.1007/s00436-010-1764-7

Blastocystis hominis is one of the most common intestinal protozoan parasites in humans, and reports have shown that blastocystosis is coupled with intestinal disorders. In the past, researchers have developed an in vitro model using B. hominis culture filtrates to investigate its ability in triggering inflammatory cytokine responses and transcription factors in human colonic epithelial cells. Studies have also correlated the inflammation by parasitic infection with cancer. The present study provides evidence of the parasite facilitating cancer cell growth through observing the cytopathic effect, cellular immunomodulation, and apoptotic responses of B. hominis, especially in malignancy. Here we investigated the effect of solubilized antigen from B. hominis on cell viability, using peripheral blood mononuclear cells (PBMCs) and human colorectal carcinoma cells (HCT116). The gene expressions of cytokines namely interleukin 6 (IL-6), IL-8, tumor necrosis factor alpha, interferon gamma, nuclear factor kappa light-chain enhancer of activated B cells (a gene transcription factor), and proapoptotic genes namely protein 53 and cathepsin B were also studied. Results exhibited favor the fact that antigen from B. hominis, at a certain concentration, could facilitate the growth of HCT116 while having the ability to downregulate immune cell responses (PBMCs). Therefore, there is a vital need to screen colorectal cancer patients for B. hominis infection as it possesses the ability to enhance the tumor growth.

Matched MeSH terms: Intercellular Signaling Peptides and Proteins/pharmacology*
Tyrisonase inhibition and melanin reduction of human melanocytes (HEMn-MP) using Anacardium occidentale L extract

Abdul Gaffar R, Abdul Majid FA, Sarmidi MR

Med J Malaysia, 2008 Jul;63 Suppl A:100-1.
PMID: 19025004

Cashew (Anacardium occindentale L) leaves extract (CLE) has potential as tyrosinase inhibitor that can be used for therapeutic in pigmentation problem. This study investigates the real potential of CLE to inhibit tyrosinase and melanin reduction using human epidermal melanocytes. The extracts were exposed to the human melanocytes for more than 24 hours. The CLE extract exhibited potential as tyrosinase inhibitor, reduced melanin and high in antioxidant activity relative to commercial extract of Emblica sp.

Matched MeSH terms: Peptides/pharmacology*
Peptide mimotopes of complex carbohydrates in Salmonella enterica serovar typhi which react with both carbohydrate-specific monoclonal antibody and polyclonal sera from typhoid patients

Thong KL, Tang SS, Tan WS, Devi S

Microbiol. Immunol., 2007;51(11):1045-52.
PMID: 18037781

Polyclonal sera from typhoid patients and a monoclonal antibody, mAb ATVi, which recognizes the capsular polysaccharide Vi antigen (ViCPS), were used to select for peptides that mimic the ViCPS by using a phage-displayed random 12-mer peptide library. Two major common mimotopes selected from the library carried the amino acid sequences TSHHDSHGLHRV and ENHSPVNIAHKL. Enzyme-linked immunosorbent assays (ELISAs) showed that these peptides carry mimotopes to ViCPS. Phage clones that contained the 12-mer peptides were also tested against pooled/individual typhoid patients' sera and found to have 3 to 5 times higher binding compared to normal sera. By using Phage-ELISA assays, the derived synthetic peptides, TSHHDSHGLHRV and ENHSPVNIAHKL, were tested against a monoclonal antibody mAb ATVi and over 2-fold difference in binding was found between these peptides and a control unrelated peptide, CTLTTKLYC. Inhibition of the mAb's binding to ViCPS indicated that the synthetic peptides successfully competed with the capsular polysaccharide for antibody binding.

Matched MeSH terms: Peptides/immunology*
Fulltext Neuroprotective Effects of Biochanin A against β-Amyloid-Induced Neurotoxicity in PC12 Cells via a Mitochondrial-Dependent Apoptosis Pathway

Tan JW, Kim MK

Molecules, 2016 Apr 25;21(5).
PMID: 27120593 DOI: 10.3390/molecules21050548

Alzheimer's disease is considered one of the major neurodegenerative diseases and is characterized by the production of β-amyloid (Aβ) proteins and progressive loss of neurons. Biochanin A, a phytoestrogen compound found mainly in Trifolium pratense, was used in the present study as a potential alternative to estrogen replacement therapy via the investigation of its neuroprotective effects against Aβ25-35-induced toxicity, as well as of its potential mechanisms of action in PC12 cells. Exposure of these cells to the Aβ25-35 protein significantly increased cell viability loss and apoptosis. However, the effects induced by Aβ25-35 were markedly reversed in the present of biochanin A. Pretreatment with biochanin A attenuated the cytotoxic effect of the Aβ25-35 protein by decreasing viability loss, LDH release, and caspase activity in cells. Moreover, we found that expression of cytochrome c and Puma were reduced, alongside with the restoration of Bcl-2/Bax and Bcl-xL/Bax ratio in the presence of biochanin A, which led to a decrease in the apoptotic rate. These data demonstrate that mitochondria are involved in the protective effect of biochanin A against Aβ25-35 and that this drug attenuated Aβ25-35-induced PC12 cell injury and apoptosis by preventing mitochondrial dysfunction. Thus, biochanin A might raise a possibility as a potential therapeutic agent for Alzheimer's disease and other related neurodegenerative diseases.

Matched MeSH terms: Amyloid beta-Peptides/toxicity*

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