RESUMO
Parasites have been associated with possible anticancer activity, including Trypanosoma cruzi, which has been linked to inhibiting the growth of solid tumors. To better understand this antitumor effect, we investigated the association of anti-T. cruzi antibodies with B cells of the acute lymphoblastic leukemia (ALL) SUPB15 cell line. The antibodies were generated in rabbits. IgGs were purified by affinity chromatography. Two procedures (flow cytometry (CF) and Western blot(WB)) were employed to recognize anti-T. cruzi antibodies on SUPB15 cells. We also used CF to determine whether the anti-T. cruzi antibodies could suppress SUPB15 cells. The anti-T. cruzi antibodies recognized 35.5% of the surface antigens of SUPB15. The complement-dependent cytotoxicity (CDC) results demonstrate the cross-suppression of anti-T. cruzi antibodies on up to 8.4% of SUPB15 cells. For the WB analysis, a band at 100 kDa with high intensity was sequenced using mass spectrometry, identifying the protein as nucleolin. This protein may play a role in the antitumor effect on T. cruzi. The anti-T. cruzi antibodies represent promising polyclonal antibodies that have the effect of tumor-suppressive cross-linking on cancer cells, which should be further investigated.
Assuntos
Anticorpos Antiprotozoários , Leucemia-Linfoma Linfoblástico de Células Precursoras , Trypanosoma cruzi , Trypanosoma cruzi/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Humanos , Linhagem Celular Tumoral , Animais , Coelhos , Anticorpos Antiprotozoários/imunologia , Proteínas de Ligação a RNA/imunologia , Proteínas de Ligação a RNA/metabolismo , Nucleolina , Fosfoproteínas/imunologia , Fosfoproteínas/metabolismoRESUMO
INTRODUCTION: Clostridioides difficile is the main cause of antibiotic-associated diarrhea in humans and is a major enteropathogen in several animal species. In newborn piglets, colonic lesions caused by C. difficile A and B toxins (TcdA and TcdB, respectively) cause diarrhea and significant production losses. OBJECTIVE: The present study aimed to develop two recombinant vaccines from immunogenic C-terminal fragments of TcdA and TcdB and evaluate the immune response in rabbits and in breeding sows. Two vaccines were produced: bivalent (rAB), consisting of recombinant fragments of TcdA and TcdB, and chimeric (rQAB), corresponding to the synthesis of the same fragments in a single protein. Groups of rabbits were inoculated with 10 or 50 µg of proteins adjuvanted with aluminum or 0.85 % sterile saline in a final volume of 1 mL/dose. Anti-TcdA and anti-TcdB IgG antibodies were detected in rabbits and sows immunized with both rAB and rQAB vaccines by ELISA. The vaccinated sows were inoculated intramuscularly with 20 µg/dose using a prime-boost approach. RESULTS: Different antibody titers (p ≤ 0.05) were observed among the vaccinated groups of sows (rAB and rQAB) and control. Additionally, newborn piglets from vaccinated sows were also positive for anti-TcdA and anti-TcdB IgGs, in contrast to control piglets (p ≤ 0.05). Immunization of sows with the rQAB vaccine conferred higher anti-TcdA and anti-TcdB responses in piglets, suggesting the superiority of this compound over rAB. CONCLUSION: The synthesized recombinant proteins were capable of inducing antibody titers against C. difficile toxins A and B in sows, and were passively transferred to piglets through colostrum.
Assuntos
Animais Recém-Nascidos , Anticorpos Antibacterianos , Toxinas Bacterianas , Vacinas Bacterianas , Clostridioides difficile , Infecções por Clostridium , Doenças dos Suínos , Vacinas Sintéticas , Animais , Feminino , Suínos , Coelhos , Infecções por Clostridium/prevenção & controle , Infecções por Clostridium/veterinária , Infecções por Clostridium/imunologia , Vacinas Bacterianas/imunologia , Vacinas Bacterianas/administração & dosagem , Vacinas Bacterianas/genética , Gravidez , Vacinas Sintéticas/imunologia , Vacinas Sintéticas/administração & dosagem , Clostridioides difficile/imunologia , Clostridioides difficile/genética , Anticorpos Antibacterianos/sangue , Toxinas Bacterianas/imunologia , Toxinas Bacterianas/genética , Doenças dos Suínos/prevenção & controle , Doenças dos Suínos/imunologia , Proteínas de Bactérias/imunologia , Proteínas de Bactérias/genética , Enterotoxinas/imunologia , Enterotoxinas/genéticaRESUMO
Antivenoms are essential in the treatment of the neurotoxicity caused by elapid snakebites. However, there are elapid neurotoxins, e.g., long-chain α-neurotoxins (also known as long-chain three-finger toxins) that are barely neutralized by commercial elapid antivenoms; so, recombinant elapid neurotoxins could be an alternative or complements for improving antibody production against the lethal long-chain α-neurotoxins from elapid venoms. This work communicates the expression of a recombinant long-chain α-neurotoxin, named HisrLcNTx or rLcNTx, which based on the most lethal long-chain α-neurotoxins reported, was constructed de novo. The gene of rLcNTx was synthesized and introduced into the expression vector pQE30, which contains a proteolytic cleavage region for exscinding the mature protein, and His residues in tandem for affinity purification. The cloned pQE30/rLcNTx was transfected into Escherichia coli Origami cells to express rLcNTx. After expression, it was found in inclusion bodies, and folded in multiple Cys-Cys structural isoforms. To observe the capability of those isoforms to generate antibodies against native long-chain α-neurotoxins, groups of rabbits were immunized with different cocktails of Cys-Cys rLcNTx isoforms. In vitro, and in vivo analyses revealed that rabbit antibodies raised against different rLcNTx Cys-Cys isoforms were able to recognize pure native long-chain α-neurotoxins and their elapid venoms, but they were unable to neutralize bungarotoxin, a classical long-chain α-neurotoxin, and other elapid venoms. The rLcNTx Cys-Cys isoform 2 was the immunogen that produced the best neutralizing antibodies in rabbits. Yet to neutralize the elapid venoms from the black mamba Dendroaspis polylepis, and the coral shield cobra Aspidelaps lubricus, it was required to use two types of antibodies, the ones produced using rLcNTx Cys-Cys isoform 2 and antibodies produced using short-chain α-neurotoxins. Expression of recombinant elapid neurotoxins as immunogens could be an alternative to improve elapid antivenoms; nevertheless, recombinant elapid neurotoxins must be well-folded to be used as immunogens for obtaining neutralizing antibodies.
Assuntos
Antivenenos , Venenos Elapídicos , Neurotoxinas , Dobramento de Proteína , Proteínas Recombinantes , Animais , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Venenos Elapídicos/imunologia , Venenos Elapídicos/genética , Venenos Elapídicos/química , Antivenenos/imunologia , Antivenenos/química , Neurotoxinas/imunologia , Neurotoxinas/genética , Neurotoxinas/química , Anticorpos Neutralizantes/imunologia , Coelhos , Sequência de AminoácidosRESUMO
Dihydroxyacetone phosphate (DHAP)-dependent aldolases catalyze the aldol addition of DHAP to a variety of aldehydes and generate compounds with two stereocenters. This reaction is useful to synthesize chiral acyclic nucleosides, which constitute a well-known class of antiviral drugs currently used. In such compounds, the chirality of the aliphatic chain, which mimics the open pentose residue, is crucial for activity. In this work, three DHAP-dependent aldolases: fructose-1,6-biphosphate aldolase from rabbit muscle, rhanmulose-1-phosphate aldolase from Thermotoga maritima, and fuculose-1-phosphate aldolase from Escherichia coli, were used as biocatalysts. Aldehyde derivatives of thymine and cytosine were used as acceptor substrates, generating new acyclic nucleoside analogues containing two new stereocenters with conversion yields between 70% and 90%. Moreover, structural analyses by molecular docking were carried out to gain insights into the diasteromeric excess observed.
Assuntos
Aldeído Liases , Escherichia coli , Frutose-Bifosfato Aldolase , Simulação de Acoplamento Molecular , Nucleosídeos de Pirimidina , Thermotoga maritima , Animais , Escherichia coli/enzimologia , Nucleosídeos de Pirimidina/química , Nucleosídeos de Pirimidina/síntese química , Aldeído Liases/metabolismo , Aldeído Liases/química , Coelhos , Frutose-Bifosfato Aldolase/química , Frutose-Bifosfato Aldolase/metabolismo , Thermotoga maritima/enzimologia , Fosfato de Di-Hidroxiacetona/metabolismo , Fosfato de Di-Hidroxiacetona/química , EstereoisomerismoRESUMO
As far as we know, no report uses the Swenson transanal endorectal pull-through technique in an animal model. Our objective is to describe the use of this technique as an experimental model for training and research purposes. Ten Norfolk hybrid rabbits were randomly selected from our experimental laboratory, with a mean weight of 3539.3 (± 678.4) g. Neither colon preparation nor fast were used before the procedures. The surgical technique was based on the description performed by Levitt et al. (2013, J Pediatr Surg. 2013;48(11):2289-2295). Information related to the surgical procedures and the clinical evolution in the postoperative period were recorded and analyzed. There were no deaths or severe complications. The anesthetic and the surgical times were significantly higher for the first three animals of the experiment. Our animal model proved adequate to perform the transanal endorectal Swenson pull-through technique, allowing the training of surgical skills through a model similar to the human, with few anesthetic complications and good postoperative evolution, including postoperative follow-up. We believe that it will serve as a learning tool in many institutions that are continuously searching for improved new techniques and will support new researches in this area.
Assuntos
Modelos Animais , Reto , Animais , Coelhos , Reto/cirurgia , Canal Anal/cirurgia , Cirurgia Endoscópica Transanal/métodos , Humanos , Duração da CirurgiaRESUMO
The volcano rabbit (Romerolagus diazi) is a lagomorph endemic to the central mountains of the Trans-Mexican Volcanic Belt and is classified as threatened at extinction risk. It is a habitat specialist in bunchgrass communities. The annual wildfires that occur throughout its distribution range are a vulnerability factor for the species. However, the effects of wildfires on volcano rabbit populations are not fully understood. We evaluated the occupancy and change in the volcano rabbit relative abundance index in the burned bunchgrass communities of the Ajusco-Chichinautzin Mountain Range during an annual cycle of wildfire events. Additionally, we assessed the factors that favor and limit occupation and reoccupation by the volcano rabbit using the relative abundance index in burned plots as an indicator of these processes. The explanatory factors for the response of the volcano rabbit were its presence in the nearby unburned bunchgrasses, the height of three species of bunchgrass communities, the proportion of different types of vegetation cover within a 500 m radius around the burned plots, heterogeneity of the vegetation cover, and the extent of the wildfire. Statistical analyses indicated possible reoccupation in less than a year in burned bunchgrass communities adjacent to unburned bunchgrass communities with volcano rabbits. The relative abundance index of volcano rabbits was not favored when the maximum height of the Muhlenbergia macroura bunchgrass community was less than 0.77 m. When the vegetation around the burned plots was dominated by forest (cover >30% of the buffer) and the fire was extensive, the number of latrines decreased per month but increased when the bunchgrass and shrub cover was greater around the burned plots. While the statistical results are not conclusive, our findings indicate a direction for future projects, considering extensive monitoring to obtain a greater number of samples that contribute to consolidating the models presented.
Assuntos
Ecossistema , Incêndios Florestais , Animais , México , Lagomorpha , Coelhos , PoaceaeRESUMO
Chronic noncommunicable diseases are a global health problem causing increased rates of mortality and sick leaves, which can be reduced by controlling dyslipidemia and hyperglycemia. Experimental and clinical studies have demonstrated the antidiabetic, lipid-lowering, antiobesogenic, anti-inflammatory, and antihypertensive properties of cinnamon; therefore, its use in yogurt can help reverse the effects of these diseases. Our study aims to evaluate the effect of a microencapsulated aqueous extract of cinnamon (Cinnamomum zeylanicum) (MCE Cz) incorporated in a yogurt drink on metabolic syndrome (MS) in a rabbit (Oryctolagus cuniculus). Physicochemical, microbiological, and proximal chemical characterization; total phenol, flavonoid, and 2,2-diphenyl-1-picrylhydrazil activity quantification; intestinal bioaccessibility; sensory analysis; MS induction through diet; and treatment with 5, 10, and 20 mg/kg of flavonoids contained in the MCE Cz were performed to help evaluate morphological, biochemical, and lipid peroxidation measurements in the liver and heart. The results show that the addition of MCE Cz in the yogurt modified the yogurt texture, increased its adhesiveness and firmness, and imparted a characteristic cinnamon color and biological value by providing intestinally bioaccessible antioxidants with antioxidant potential by reducing lipoperoxidation in the liver and heart after treatment. MCE Cz reduced the weight of the animals by up to 38.5% and the abdominal circumference by 29%. Biochemically, it decreased glucose levels by 24.38%, total cholesterol levels by 69.2%, triglyceride levels by 72.69%, and low-density lipoprotein levels by 89.25%; it increased high-density lipoprotein levels by 67.08%. Therefore, adding MCE Cz in doses of 5 and 10 mg of flavonoids in drinkable yogurt can be an alternative to preparing functional foods with physicochemical attributes and biological properties that can be consumed at all stages of life without undesirable effects. Moreover, it can act as a potential adjuvant in the treatment of comorbidities related to MS.
Assuntos
Cinnamomum zeylanicum , Síndrome Metabólica , Extratos Vegetais , Iogurte , Animais , Coelhos , Cinnamomum zeylanicum/química , Síndrome Metabólica/dietoterapia , Iogurte/análise , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Masculino , Alimentos Fortificados/análise , Flavonoides/análise , Flavonoides/administração & dosagem , Composição de Medicamentos , HumanosRESUMO
BACKGROUND: Wound healing monitoring and timely decision-making are critical for wound classification. Tryptophan (Tr) intrinsic fluorescence, detected at 295/340 nm, provides a noninvasive approach for wound assessment. Our previous work demonstrated that this autofluorescence is associated with keratinocytes in a highly proliferative state in vitro. OBJECTIVE: We investigated the correlation between Tr fluorescence and key wound healing parameters, including re-epithelialization, fibrosis, neovascularization, and acute and chronic inflammation, using a rabbit model. METHODS: Seven rabbits underwent wound healing assessment over a 15-day period. We employed histological analysis from central and marginal biopsies, and UV fluorescence imaging captured by a monochromatic near-UV sensitive camera equipped with a passband optical filter (340 nm/12 nm). Excitation was achieved using a 295 nm LEDs ring lamp. Normalized fluorescence values were correlated with histological measurements using Pearson correlation. RESULTS: The UV fluorescence strongly exhibited a strong correlation with re-epithelization (r = 0.8) at the wound edge, with peak intensity observed between the sixth and ninth days. Notably, wound-healing dynamics differed between the wound center and edge, primarily attributed to variations in re-epithelialization, neovascularization, and chronic inflammation. CONCLUSION: Our findings highlight the presence of autofluorescence at 295/340 nm during wound healing, demonstrating a robust association with re-epithelialization. This excitation/emission signal holds promise as a valuable noninvasive strategy for monitoring wound closure, re-epithelialization, and other biological processes where Tr plays a pivotal role.
Assuntos
Reepitelização , Triptofano , Cicatrização , Animais , Coelhos , Reepitelização/fisiologia , Cicatrização/fisiologia , Modelos Animais de Doenças , Fluorescência , Pele/patologia , Pele/lesões , Imagem Óptica/métodos , Inflamação/patologia , Raios UltravioletaRESUMO
The byproduct of Salvia hispanica (chia) seed oil extraction by cold pressing, also known as expeller, possesses a high nutritional value. It is rich in proteins, fibers, minerals, and has a residual oil content of 7-11%, which is rich in omega 3 linolenic acid (ALA). However, this byproduct has been historically undervalued. Thus, the aim of current work was to study the effects of consuming of a rich in chia expeller diet on a rabbit model of metabolically unhealthy normal weight to validate their use as a functional food. Rabbits were fed different diets for a period of 6 weeks: a standard diet (CD), a high-fat diet (HFD), a rich in expeller CD (Exp-CD) and a rich in expeller HFD (Exp-HFD). The Exp-HFD attenuated the rise in basal glucose, TyG index, triglycerides, cholesterol and non-HDL cholesterol induced by the HFD. Both rich in expeller diets reduced mean arterial blood pressure (MAP) and increase liver and fat ALA levels compared to their respective controls. Furthermore, the angiotensin converting enzyme (ACE) activity was lower in the lungs of animals fed on rich in expeller diets compared to their respective controls. In vitro studies showed that ALA inhibited ACE activity. The evaluation of vascular reactivity revealed that rich in expeller diets improved angiotensin II affinity and reduced contractile response to noradrenaline. In conclusion, the consumption of rich in expeller diets showed beneficial effects in preventing cardiovascular risk factors such as insulin resistance, dyslipidemia and MAP. Therefore, its use as functional ingredient holds significant promise.
Assuntos
Dieta Hiperlipídica , Óleos de Plantas , Salvia hispanica , Sementes , Animais , Coelhos , Sementes/química , Óleos de Plantas/farmacologia , Dieta Hiperlipídica/efeitos adversos , Masculino , Pressão Sanguínea/efeitos dos fármacos , Fatores de Risco de Doenças Cardíacas , Triglicerídeos/sangue , Triglicerídeos/metabolismo , Doenças Cardiovasculares/prevenção & controle , Ácido alfa-Linolênico/farmacologia , Modelos Animais de Doenças , Alimento Funcional , Fígado/efeitos dos fármacos , Fígado/metabolismo , Glicemia/metabolismo , Glicemia/efeitos dos fármacos , Colesterol/sangue , Salvia/química , Valor NutritivoRESUMO
OBJECTIVE: To compare the effect of submucosal cryotherapy using cold saline to dexamethasone sodium phosphate and diclofenac sodium injections on substance P and interleukin 6 release in experimentally induced pulpal inflammation in rabbits' molar teeth. METHODOLOGY: Fifteen rabbits were randomly classified into 3 groups according to the submucosal injection given: cold saline, dexamethasone sodium phosphate, and diclofenac sodium. A split-mouth design was adopted, the right mandibular molars were experimental, and the left molars served as the control without injections. Intentional pulp exposures were created and left for 6 hours to induce pulpitis. Pulpal tissue was extracted and examined for SP and IL-6 levels using ELISA. Within each group, the level of cytokines released was measured for both control and experimental groups for intragroup comparison to determine the effect of injection. The percentage reduction of each mediator was calculated compared with the control side for intergroup comparison then the correlation between SP and IL-6 levels was analyzed using Spearman's rank order correlation coefficient. Statistical analysis was performed, and the significance level was set at p<0.05. RESULTS: Submucosal cryotherapy, dexamethasone sodium phosphate, and diclofenac sodium significantly reduced SP and IL-6 pulpal release. Submucosal cryotherapy significantly reduced SP more than and IL-6 more than dexamethasone sodium phosphate and diclofenac sodium. Pulpal reduction of SP and IL-6 showed a strong positive significant correlation. CONCLUSIONS: Submucosal cryotherapy reduces the pulpal release of SP and IL-6 and could be tested as an alternative to premedication to potentiate the effect of anesthesia and control postoperative endodontic pain.