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1.
J Tradit Complement Med ; 13(5): 521-529, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37693101

RESUMO

Lower urinary tract symptoms (LUTS) resulting from benign prostatic hyperplasia are a common complaint among elderly men worldwide. Our previous study reported alleviative efficacy of Thai traditional massage (TTM) on LUTS patients. However, underlying mechanism at cellular level remained elusive. Herein, we investigated the effect of TTM on urinary monocyte chemotactic protein-1 (MCP-1) and associative inflammatory biomarkers. Forty-three patients were randomized into two groups: Tamsulosin (n = 23) and TTM (n = 20). The urinary MCP-1 and interferon-gamma (IFN-γ) levels as well as gene expression levels of MCP-1, Chemotactic protein receptor 2b (CCR2b), IFN-γ, interleukin-1 beta (IL-1ß), and transforming growth factor-beta 1 (TGF-ß1) were evaluated before and after a four-week treatment. The urinary MCP-1 and IFN-γ levels as well as gene expression levels of MCP-1, CCR2b, IFN-γ, IL-1ß, and TGF-ß1 were evaluated before and after treatment with Tamsulosin or TTM group. Urinary MCP-1 and IFN-γ levels and the expression levels of five genes from sedimented urine samples were measured using Enzyme-Linked Immunosorbent Assay and quantitative Reverse Transcription Polymerase Chain Reaction, respectively. We observed significant (p < 0.05) reduction in the ratio of urinary MCP-1 and creatinine (Cr); MCP-1/Cr levels in subjects given only TTM. There were no significant differences (p < 0.05) in IFN-γ/Cr levels in both groups. TTM group down-regulated the expression of IFN-γ whereas up-regulated IL-1ß and TGF-ß1 mRNA. Our findings suggested TTM had alleviative effects in LUTS patients, which were partially mediated by a reduction of urinary inflammatory cytokines and inflammatory gene expression.

2.
Pharmaceuticals (Basel) ; 16(2)2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-37259384

RESUMO

Lysiphyllum strychnifolium (Craib) A. Schmitz (LS) has been traditionally used as a medicinal herb by folk healers in Thailand with rare evidence-based support. Hepatic cytochrome P450s (CYPs450) are well known as the drug-metabolizing enzymes that catalyze all drugs and toxicants. In this study, we investigated the mRNA levels of six clinically important CYPs450, i.e., CYP1A2, 3A2, 2C11, 2D1, 2D2, and 2E1, in rats given LS extracts. Seventy Wistar rats were randomized into seven groups (n = 10). Each group was given LS stem ethanol (SE) and leaf water (LW) extracts orally at doses of 300, 2000, and 5000 mg/kg body weight (mg/kg.bw) for twenty-eight consecutive days. After treatment, the expression of CYPs450 genes was measured using quantitative real-time PCR. The results revealed that SE and LW, which contained quercetin and gallic acid, promoted the upregulation of all CYPs450. Almost all CYPs450 genes were downregulated in all male LW-treated rats but upregulated in female-treated groups, suggesting that CYP gene expressions in LS-treated rats were influenced by gender. Moderate and high doses of the LS extracts had a tendency to induce six CYP450s' transcription levels in both rat genders. CYP2E1 gene showed a unique expression level in male rats receiving SE at a dose of 2000 mg/kg.bw, whereas a low dose of 300 mg/kg.bw was found in the LW-treated female group. As a result, our findings suggest that different doses of LS extracts can moderate the varying mRNA expression of clinically relevant CYP genes. In this study, we provide information about CYP induction and inhibition in vivo, which could be a desirable condition for furthering the practical use of LS extracts in humans.

3.
In Vivo ; 37(1): 286-293, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36593062

RESUMO

BACKGROUND/AIM: Vitamin D3 (VD3) affects the regulation of the immune system, including the differentiation and function of regulatory T-cells (Tregs). Tregs play an important role in maintaining immune homeostasis in patients with colorectal cancer (CRC). The effects of VD3 on Treg-associated immune function were investigated in Thai patients in the early stages of CRC. MATERIALS AND METHODS: Twenty-eight patients were randomized to one of two groups: Untreated or treatment with VD3 for 3 months. Whole blood samples were collected at baseline, and at 1 and 3 months. Peripheral blood mononuclear cells were isolated and the populations of forkhead box P3-positive Treg cells was analyzed by flow cytometry. The levels of Treg-associated cytokines, interleukin 10 (IL-10) and transforming growth factor beta 1 (TGF-ß1), were measured by enzyme-linked immunosorbent assays. RESULTS: Serum VD3 levels of the VD3-treated group were significantly increased at 1 (p=0.017) and 3 months (p<0.001) compared to the untreated control group. The mean percentage of Tregs was maintained between 1 and 3 months in the VD3-treated group. At 3 months, the untreated group had significantly lower Treg levels than the VD3-treated group (p=0.043). Serum IL-10 levels of the VD3-treated group were statistically increased at 1 month compared to the control group (p=0.032). No significant difference in serum TGF-ß1 levels was observed between the two groups. However, the TGF-ß1 level in the VD3-treated group at 1 month was lower than that of the control. CONCLUSION: Our findings suggest that VD3 supplementation can maintain immune responses in the early stages of CRC, helping to control Treg function. Therefore, VD3 should be supplemented to maintain immune homeostasis, especially in patients with vitamin D deficiency.


Assuntos
Colecalciferol , Neoplasias Colorretais , Linfócitos T Reguladores , Humanos , Colecalciferol/administração & dosagem , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/cirurgia , Suplementos Nutricionais , Homeostase , Interleucina-10/imunologia , Leucócitos Mononucleares/imunologia , Linfócitos T Reguladores/imunologia , Fator de Crescimento Transformador beta1/imunologia
4.
Molecules ; 27(12)2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35745006

RESUMO

Thunbergia laurifolia (TL) has been traditionally used as an antidote and an antipyretic drug by folk healers for centuries in Thailand. Rosmarinic acid (RA) is major compound in TL extract and has attracted great interest due to its potential broad pharmacological effects. Herein, the permeability of RA was investigated in TL extract and as a pure compound in a Caco-2 cell model by using high-performance liquid chromatography with a photodiode array detector (HPLC-PDA). The results reveal that the apparent permeability coefficient (Papp) values of RA in TL extracts and pure RA significantly increased after deconjugation by ß-glucuronidase/sulfatase enzymes. Our findings exhibit possible saturable biotransformation of RA and/or membrane transport while penetrated through Caco-2 cells. The cumulative amounts of RA as pure compounds and in TL extracts increased with the exposure time, and the efflux ratio (ER) was 0.27-1.14. RA in the TL extract has a similar absorption in the conjugated form and in the pure compound. The intestinal absorption of them is through passive diffusion. Therefore, our findings conclude that the intestinal transport of RA in TL extracts was mainly penetrated as conjugated forms with glucuronic acid and/or sulfate across Caco-2 cells and transported via passive diffusion.


Assuntos
Acanthaceae , Água , Células CACO-2 , Cinamatos , Depsídeos , Humanos , Absorção Intestinal , Permeabilidade , Folhas de Planta/química , Água/análise
6.
Artigo em Inglês | MEDLINE | ID: mdl-30181738

RESUMO

BACKGROUND: Fire ant venom is a complex mixture consisting of basic piperidine alkaloids, various biologically active peptides and protein components, including a variety of major allergenic proteins. Tropical fire ant Solenopsis geminata is an important stinging ant species that causes anaphylaxis and serious medical problems. Although the biological activities of allergenic venom proteins that are unique to ant venom, particularly Solenopsis 2 and 4, are still unknown, these proteins are believed to play important roles in mediating the effects of the piperidine derivatives in the venom. METHODS: In the present study, the cDNA cloning, sequencing and three-dimensional structure of Sol g 4.1 venom protein are described. The recombinant Sol g 4.1 protein (rSol g 4.1) was produced in E. coli, and its possible function as a hydrophobic binding protein was characterized by paralyzing crickets using the 50% piperidine dose (PD50). Moreover, an antiserum was produced in mice to determine the allergenic properties of Sol g 4.1, and the antiserum was capable of binding to Sol g 4.1, as determined by Western blotting. RESULTS: The molecular weight of Sol g 4.1 protein is 16 kDa, as determined by SDS-PAGE. The complete cDNA is 414 bp in length and contains a leader sequence of 19 amino acids. The protein consists of six cysteines that presumably form three disulfide bonds, based on a predicted three-dimensional model, creating the interior hydrophobic pocket and stabilizing the structure. The rSol g 4.1 protein was expressed in inclusion bodies, as determined by SDS-PAGE. Dialysis techniques were used to refold the recombinant protein into the native form. Its secondary structure, which primarily consists of α-helices, was confirmed by circular dichroism analysis, and the three-dimensional model was also verified. The results of allergenic analysis performed on mice showed that the obtained protein was predicted to be allergenically active. Moreover, we report on the possible role of the Sol g 4.1 venom protein, which significantly reduced the PD50 from 0.027 to 0.013% in paralyzed crickets via synergistic effects after interactions with piperidine alkaloids. CONCLUSIONS: The primary structure of Sol g 4.1 showed high similarity to that of venom proteins in the Solenopsis 2 and 4 family. Those proteins are life-threatening and produce IgE-mediated anaphylactic reactions in allergic individuals. The possible function of this protein is the binding of the interior hydrophobic pockets with piperidine alkaloids, as determined by the analysis of the structural model and PD50 test.

7.
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-954859

RESUMO

Fire ant venom is a complex mixture consisting of basic piperidine alkaloids, various biologically active peptides and protein components, including a variety of major allergenic proteins. Tropical fire ant Solenopsis geminata is an important stinging ant species that causes anaphylaxis and serious medical problems. Although the biological activities of allergenic venom proteins that are unique to ant venom, particularly Solenopsis 2 and 4, are still unknown, these proteins are believed to play important roles in mediating the effects of the piperidine derivatives in the venom. Methods: In the present study, the cDNA cloning, sequencing and three-dimensional structure of Sol g 4.1 venom protein are described. The recombinant Sol g 4.1 protein (rSol g 4.1) was produced in E. coli , and its possible function as a hydrophobic binding protein was characterized by paralyzing crickets using the 50% piperidine dose (PD50). Moreover, an antiserum was produced in mice to determine the allergenic properties of Sol g 4.1, and the antiserum was capable of binding to Sol g 4.1, as determined by Western blotting. Results: The molecular weight of Sol g 4.1 protein is 16 kDa, as determined by SDS-PAGE. The complete cDNA is 414 bp in length and contains a leader sequence of 19 amino acids. The protein consists of six cysteines that presumably form three disulfide bonds, based on a predicted three-dimensional model, creating the interior hydrophobic pocket and stabilizing the structure. The rSol g 4.1 protein was expressed in inclusion bodies, as determined by SDS-PAGE. Dialysis techniques were used to refold the recombinant protein into the native form. Its secondary structure, which primarily consists of α-helices, was confirmed by circular dichroism analysis, and the three-dimensional model was also verified. The results of allergenic analysis performed on mice showed that the obtained protein was predicted to be allergenically active. Moreover, we report on the possible role of the Sol g 4.1 venom protein, which significantly reduced the PD50 from 0.027 to 0.013% in paralyzed crickets via synergistic effects after interactions with piperidine alkaloids. Conclusions: The primary structure of Sol g 4.1 showed high similarity to that of venom proteins in the Solenopsis 2 and 4 family. Those proteins are life-threatening and produce IgE-mediated anaphylactic reactions in allergic individuals. The possible function of this protein is the binding of the interior hydrophobic pockets with piperidine alkaloids, as determined by the analysis of the structural model and PD50 test.(AU)


Assuntos
Produtos Biológicos , Proteínas Recombinantes , Venenos de Formiga
8.
J. venom. anim. toxins incl. trop. dis ; 24: 1-13, 2018. tab, ilus, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1484756

RESUMO

Background: Fire ant venom is a complex mixture consisting of basic piperidine alkaloids, various biologically active peptides and protein components, including a variety of major allergenic proteins. Tropical fire ant Solenopsis geminata is an important stinging ant species that causes anaphylaxis and serious medical problems. Although the biological activities of allergenic venom proteins that are unique to ant venom, particularly Solenopsis 2 and 4, are still unknown, these proteins are believed to play important roles in mediating the effects of the piperidine derivatives in the venom. Methods: In the present study, the cDNA cloning, sequencing and three-dimensional structure of Sol g 4.1 venom protein are described. The recombinant Sol g 4.1 protein (rSol g 4.1) was produced in E. coli , and its possible function as a hydrophobic binding protein was characterized by paralyzing crickets using the 50% piperidine dose (PD50). Moreover, an antiserum was produced in mice to determine the allergenic properties of Sol g 4.1, and the antiserum was capable of binding to Sol g 4.1, as determined by Western blotting. Results: The molecular weight of Sol g 4.1 protein is 16 kDa, as determined by SDS-PAGE. The complete cDNA is 414 bp in length and contains a leader sequence of 19 amino acids. The protein consists of six cysteines that presumably form three disulfide bonds, based on a predicted three-dimensional model, creating the interior hydrophobic pocket and stabilizing the structure. The rSol g 4.1 protein was expressed in inclusion bodies, as determined by SDS-PAGE. Dialysis techniques were used to refold the recombinant protein into the native form. Its secondary structure, which primarily consists of -helices, was confirmed by circular dichroism analysis, and the three-dimensional model was also verified. The results of allergenic analysis performed on mice showed that the...


Assuntos
Animais , Alérgenos , Formigas/química , Proteínas/química , Venenos de Formiga/química
9.
Artigo em Inglês | MEDLINE | ID: mdl-27790249

RESUMO

BACKGROUND: Wasp venom is a complex mixture containing proteins, enzymes and small molecules, including some of the most dangerous allergens. The greater banded wasp (Vespa tropica) is well-known for its lethal venom, whose one of the major components is a hyaluronidase (HAase). It is believed that the high protein proportion and activity of this enzyme is responsible for the venom potency. METHODS: In the present study, cDNA cloning, sequencing and 3D-structure of Vespa tropica venom HAase were described. Anti-native HAase antibody was used for neutralization assay. RESULTS: Two isoforms, VesT2a and VesT2b, were classified as members of the glycosidase hydrolase 56 family with high similarity (42-97 %) to the allergen venom HAase. VesT2a gene contained 1486 nucleotide residues encoding 357 amino acids whereas the VesT2b isoform consisted of 1411 residues encoding 356 amino acids. The mature VesT2a and VesT2b are similar in mass and pI after prediction. They are 39119.73 Da/pI 8.91 and 39571.5 Da/pI 9.38, respectively. Two catalytic residues in VesT2a, Asp107 and Glu109 were substituted in VesT2b by Asn, thus impeding enzymatic activity. The 3D-structure of the VesT2s isoform consisted of a central core (α/ß)7 barrel and two disulfide bridges. The five putative glycosylation sites (Asn79, Asn99, Asn127, Asn187 and Asn325) of VesT2a and the three glycosylation sites (Asn1, Asn66 and Asn81) in VesT2b were predicted. An allergenic property significantly depends on the number of putative N-glycosylation sites. The anti-native HAase serum specifically recognized to venom HAase was able to neutralize toxicity of V. tropica venom. The ratio of venom antiserum was 1:12. CONCLUSIONS: The wasp venom allergy is known to cause life-threatening and fatal IgE-mediated anaphylactic reactions in allergic individuals. Structural analysis was a helpful tool for prediction of allergenic properties including their cross reactivity among the vespid HAase.

10.
Toxicon ; 119: 159-67, 2016 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-27288895

RESUMO

Vespid venom is composed of many bioactive compounds. The venom of the banded tiger wasp (Vespa affinis, or VA) and the great banded wasp (Vespa tropica, or VT)-which are locally found in the northeastern part of Thailand and are well known for their life-threatening venom potency-were comparatively studied in terms of potency, composition and biological activity. Clinical studies that included word-of-mouth information shared by traditional healers in local areas noted that the venom of VT is more potent than that of VA. Our previous study showed that the venom of VA is lower in potency (PD50 = 12.5 µg/g body weight) than that of VT (PD50 = 3 µg/g body weight). Analysis with the PAGE technique showed that these two venoms showed similar patterns of active proteins. Most protein spots were basic proteins at an isoelectric point (pI) ranging from 5 to 10, with molecular weights between 27 and 50 kDa. These spots were identified as hyaluronidase, phospholipase, antigen 5, dipeptidyl peptidase and albumin-like protein. The proportion of hyaluronidase was 2.5 times higher in VT than in VA. VT also showed higher hyaluronidase, phospholipase and dipeptidyl peptidase activities, suggesting that these components made VT venom more potent than VA venom.


Assuntos
Proteômica , Venenos de Vespas/química , Animais , Eletroforese em Gel de Poliacrilamida , Espectrometria de Massas , Venenos de Vespas/classificação
11.
J. venom. anim. toxins incl. trop. dis ; 22: 28, 2016. tab, graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-954789

RESUMO

Background: Wasp venom is a complex mixture containing proteins, enzymes and small molecules, including some of the most dangerous allergens. The greater banded wasp (Vespa tropica) is well-known for its lethal venom, whose one of the major components is a hyaluronidase (HAase). It is believed that the high protein proportion and activity of this enzyme is responsible for the venom potency. Methods: In the present study, cDNA cloning, sequencing and 3D-structure of Vespa tropica venom HAase were described. Anti-native HAase antibody was used for neutralization assay. Results: Two isoforms, VesT2a and VesT2b, were classified as members of the glycosidase hydrolase 56 family with high similarity (42-97 %) to the allergen venom HAase. VesT2a gene contained 1486 nucleotide residues encoding 357 amino acids whereas the VesT2b isoform consisted of 1411 residues encoding 356 amino acids. The mature VesT2a and VesT2b are similar in mass and pI after prediction. They are 39119.73 Da/pI 8.91 and 39571.5 Da/pI 9.38, respectively. Two catalytic residues in VesT2a, Asp107 and Glu109 were substituted in VesT2b by Asn, thus impeding enzymatic activity. The 3D-structure of the VesT2s isoform consisted of a central core (α/β)7 barrel and two disulfide bridges. The five putative glycosylation sites (Asn79, Asn99, Asn127, Asn187 and Asn325) of VesT2a and the three glycosylation sites (Asn1, Asn66 and Asn81) in VesT2b were predicted. An allergenic property significantly depends on the number of putative N-glycosylation sites. The anti-native HAase serum specifically recognized to venom HAase was able to neutralize toxicity of V. tropica venom. The ratio of venom antiserum was 1:12. Conclusions: The wasp venom allergy is known to cause life-threatening and fatal IgE-mediated anaphylactic reactions in allergic individuals. Structural analysis was a helpful tool for prediction of allergenic properties including their cross reactivity among the vespid HAase.(AU)


Assuntos
Animais , Venenos de Vespas , Vespas , Clonagem de Organismos , Glicosídeo Hidrolases , Hialuronoglucosaminidase
12.
J. venom. anim. toxins incl. trop. dis ; 22: [1-11], 2016. ilus, tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1484667

RESUMO

Wasp venom is a complex mixture containing proteins, enzymes and small molecules, including some of the most dangerous allergens. The greater banded wasp (Vespa tropica) is well-known for its lethal venom, whose one of the major components is a hyaluronidase (HAase). It is believed that the high protein proportion and activity of this enzyme is responsible for the venom potency. Methods: In the present study, cDNA cloning, sequencing and 3D-structure of Vespa tropica venom HAase were described. Anti-native HAase antibody was used for neutralization assay. Results: Two isoforms, VesT2a and VesT2b, were classified as members of the glycosidase hydrolase 56 family with high similarity (4297 %) to the allergen venom HAase. VesT2a gene contained 1486 nucleotide residues encoding 357 amino acids whereas the VesT2b isoform consisted of 1411 residues encoding 356 amino acids. The mature VesT2a and VesT2b are similar in mass and pI after prediction. They are 39119.73 Da/pI 8.91 and 39571.5 Da/pI 9.38, respectively. Two catalytic residues in VesT2a, Asp107 and Glu109 were substituted in VesT2b by Asn, thus impeding enzymatic activity. The 3D-structure of the VesT2s isoform consisted of a central core (/)7 barrel and two disulfide bridges. The five putative glycosylation sites (Asn79, Asn99, Asn127, Asn187 and Asn325) of VesT2a and the three glycosylation sites (Asn1, Asn66 and Asn81) in VesT2b were predicted. An allergenic property significantly depends on the number of putative N-glycosylation sites. The anti-native HAase serum specifically recognized to venom HAase was able to neutralize toxicity of V. tropica venom. The ratio of venom antiserum was 1:12. Conclusions: The wasp venom allergy is known to cause life-threatening and fatal IgE-mediated anaphylactic reactions in allergic individuals. Structural analysis was a helpful tool for prediction of allergenic properties including their cross reactivity among the vespid HAase.


Assuntos
Animais , Hialuronoglucosaminidase/análise , Hialuronoglucosaminidase/classificação , Hialuronoglucosaminidase/toxicidade , Venenos de Vespas/administração & dosagem , Venenos de Vespas/análise , Venenos de Vespas/toxicidade
13.
Biochem Genet ; 52(11-12): 459-73, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24980735

RESUMO

Heteroscorpine-1 (HS-1) was identified as a member of the scorpine family. HS-1 shows insecticidal activities, exhibiting a low median lethal dose (LD50) in mealworm (Tenebrio molitor L.) and inhibitory activities against Bacillus subtilis, Klebsiella pneumoniae, and Pseudomonas aeruginosa. In this study, a recombinant HS-1 (rHS-1) was produced by overexpression in E. coli. A large yield of product was obtained. The structure of purified rHS-1 was confirmed through mass spectrometry. Both anti-crude venom and anti-rHS-1 antibodies specifically recognized rHS-1, suggesting its structural similarity. Reactivated rHS-1 caused roughening and blebbing of bacterial cell surfaces. It showed higher activity than that of pre-refolded protein. Antisera raised against a partially purified and mis- or unfolded peptide can inhibit relevant bioactivity.


Assuntos
Antibacterianos/farmacologia , Antivenenos , Venenos de Escorpião/farmacologia , Animais , Anticorpos Neutralizantes/imunologia , Reações Cruzadas , Inseticidas , Redobramento de Proteína , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/farmacologia , Venenos de Escorpião/genética , Venenos de Escorpião/imunologia , Tenebrio
14.
Toxicon ; 61: 62-71, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23142507

RESUMO

Heteromtoxin (HmTx) is a group III phospholipase A(2) produced in Heterometrus laoticus, in Thailand. In this study, HmTx was purified from venom by separation chromatography, and the PLA(2) activity of the fractions was determined by lecithin agar assay. The enzyme is an acidic protein with a pI of 5.6 and an apparent molecular weight of 14018.4 Da. The nucleotide sequence of HmTx contains 649 bp, and the mature protein is predicted to have 131 amino acid residues-104 of which make up the large subunit, and 27 of which make up the small subunit. The subunit structure of HmTx is highly similar to that of the other toxin, Pandinus imperator imperatoxin I (IpTx(i)) and to Mesobuthus tamulus phospholipase A(2) (MtPLA(2)). The 3D-structure of HmTx consists of three conserved alpha-helices: h1 (Lys24-His34), h2 (Cys59-Asp71), and h3 (Ala80-Phe89). The beta-sheet consisted of a single stranded anti-parallel beta-sheet (b1.1 at Glu43-Lys45 and b1.2 at Lys48-Asn50) that was highly similar to the conserved sequences (-CGXG-, -CCXXHDXC- and CXCEXXXXXC-) of Apis mellifera (bee) phospholipases.


Assuntos
Fosfolipases A2/química , Venenos de Escorpião/enzimologia , Escorpiões/química , Sequência de Aminoácidos , Animais , DNA Complementar/genética , Eletroforese em Gel de Poliacrilamida , Modelos Genéticos , Modelos Moleculares , Dados de Sequência Molecular , Peso Molecular , Fosfolipases A2/genética , Filogenia , Venenos de Escorpião/genética , Escorpiões/genética , Homologia de Sequência de Aminoácidos
15.
Toxicon ; 61: 151-64, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23159790

RESUMO

The Thai banded tiger wasp (Vespa affinis) is one of the most dangerous vespid species in Southeast Asia, and stinging accidents involving this species still cause fatalities. In the present study, four forms of V. affinis phospholipase A(1) were identified through a proteomics approach. Two of these enzymes were purified by reverse-phase chromatography, and their biochemical properties were characterised. These enzymes, designated Ves a 1s, are not glycoproteins and exist as 33441.5 and 33474.4 Da proteins, which corresponded with the 34-kDa band observed via SDS-PAGE. The thermal stabilities of these enzymes were stronger than snake venom. Using an in vivo assay, no difference was found in the toxicities of the different isoforms. Furthermore, the toxicity of these enzymes does not appear to be correlated with their PLA(1) activity. The cDNAs of the full-length version of Ves a 1s revealed that the Ves a 1 gene consists of a 1005-bp ORF, which encodes 334 amino acid residues, and 67- and 227-bp 5' and 3' UTRs, respectively. The two isoforms are different by three nucleotide substitutions, resulting in the replacement of two amino acids. Through sequence alignment, these enzymes were classified as members of the pancreatic lipase family. The structural modelling of Ves a 1 used the rat pancreatic lipase-related protein 2 (1bu8A) as a template because it has PLA(1) activity, which demonstrated that this enzyme belongs to the α/ß hydrolase fold family. The Ves a 1 structure, which is composed of seven α-helixes and eleven ß-strands, contains the ß-strand/ɛSer/α-helix structural motif, which contains the Gly-X-Ser-X-Gly consensus sequence. The typical surface structures that play important roles in substrate selectivity (the lid domain and the ß9 loop) were shortened in the Ves a 1 structure, which suggests that this enzyme may only exhibit phospholipase activity. Moreover, the observed insertion of proline into the lid domain of the Ves a 1 structure is rare. We therefore propose that this proline residue might be involved in the stability and activity of Ves a 1s.


Assuntos
Fosfolipases A1/química , Venenos de Vespas/enzimologia , Vespas/química , Animais , Sequência de Bases , Cromatografia Líquida de Alta Pressão , DNA Complementar/genética , Bases de Dados Factuais , Relação Dose-Resposta a Droga , Eletroforese em Gel de Poliacrilamida , Gryllidae , Isoenzimas/química , Espectrometria de Massas , Modelos Moleculares , Dados de Sequência Molecular , Peso Molecular , Paralisia/induzido quimicamente , Fosfolipases A1/genética , Fosfolipases A1/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Tailândia , Venenos de Vespas/química
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