Enhancing effects of Aloe vera gel extracts on the humoral and cellular immune response and growth performance in broiler chickens.

Objective: The experiment evaluated how Aloe vera gel (AVG) extract supplementation affected immune responses and physiological performances in broiler chickens. Materials and Methods: 90-day-old Cobb 500 broiler chicks were reared for 38 days without the addition of antibiotics, either through feed or water. At 10 days, chicks were allocated into three groups: A, B, and C (n = 30). Group A served as non-supplemented control. Groups B and C were administered aqueous extracts of AVG at 1.0% and 2.0%, respectively, with drinking water. Results: The supplementation of AVG potentiated the chicken immune response to Newcastle disease-vaccinated birds and sheep red blood cell-treated birds, which detected the highest antibody titers against Newcastle disease virus and sRBC. The cellular immune response evaluated through a cutaneous basophilic hypersensitivity test using phytohemagglutinin-P demonstrated a significant increase in skin thickness in AVG-supplemented birds. The relative sizes of lymphoid organs (bursa, spleen, and thymus) were significantly enhanced (p < 0.05) among the groups. Broilers given AVG-1 and AVG-2 exhibited significantly greater (p < 0.01) live body weight, dressing percentages, and serum protein and serum albumin levels. The supplemented groups experienced a significant reduction in total serum cholesterol, triglycerides, and low-density lipoprotein-cholesterol values, while the levels of high-density lipoprotein-cholesterol remained unchanged. The dietary aqueous extracts of AVG are effective in enhancing innate and specific immunity. Conclusion: This work strengthens the perspective of the use of AVG as an immune stimulant to facilitate recovery from immune suppression states, enhance innate and specific immunity, and improve broiler growth performance.

Detection and quantification of heavy metals and minerals in poultry feed collected from selected local markets in Bangladesh.

Objective: The study was primarily conducted to assess the stakeholders' knowledge regarding the contamination caused by heavy metals in poultry feedstuffs. The concentration of some heavy metals (lead, chromium, cadmium, and nickel) and macro-minerals (sodium, potassium, and calcium) was also analyzed in poultry feeds collected from selected local markets in Sherpur district, Bangladesh. Materials and Methods: A well-structured questionnaire survey was used to investigate different stakeholders' perspectives in relation to metal contamination in feed. Heavy metals and calcium were determined by atomic absorption spectrophotometry. The flame emission spectrophotometric technique was applied to determine sodium and potassium. Results: The majority of the stakeholders (90%) were found to have no knowledge regarding heavy metal contamination. Lead and nickel concentrations were below the detectable level in the collected samples. The average concentration of chromium in Jhenaigati upazila was four times higher than in Nalitabari upazila, at 21.806 mg kg-1 and 5.452 mg kg-1, respectively. The concentrations of cadmium in both brand and nonbrand samples exceeded the maximum allowable limit set by the European Union at 1.329 mg kg-1 and 1.328 mg kg-1, respectively. Sodium, potassium, and calcium were found in the ranges of 0.0011%-0.0035%, 0.0010%-0.0013%, and 0.0080%-0.0305%, which were extremely low in concentration compared to the minimum requirement in poultry feed. Conclusion: Regular surveillance and governance systems should be incorporated into national policy to cease the hazardous impacts of heavy metals through feed contamination. From a nutritional viewpoint, poultry feeds need to be critically formulated.

Exposure to environmentally relevant phthalate mixture during pregnancy alters the physical and hemato-biochemical parameters in Black Bengal goats.

Several environmental pollutants, mostly chemicals and plasticizers, have an effect on the reproduction of small ruminants, causing abortion, delayed estrus, and decreased fertility. Phthalates are common in our environment and have been identified as endocrine disrupting chemicals (EDCs). The research work investigated the impact of dietary exposure to a phthalate mixture on physical and hemato-biochemical parameters in pregnant Black Bengal (BB) goats. A total of 20 clinically healthy, 1-2 months pregnant, aged 6-8 months with a body weight of 10-12 kg BB goats were collected and divided into two (n = 10) groups. The treatment group received a standard goat ration with a combination of different phthalates mixture while the control group was provided the same ration with the vehicle of aphthalatemixture until parturition. The physical parameters were measured with appropriate tools and blood samples were collected for hemato-biochemical tests. The results showed that the physiological parameters (body condition score, respiration rate and heart rate) were significantly (P < 0.05) reduced in phthalate-exposed goats without altering rectal temperature and rumen motility. The hematological parameters: RBC count, WBC count, hemoglobin concentration, hematocrit values and RBC indices were significantly (P < 0.05) lower in phthalate-exposed goats. Phthalate-exposed BB goats had significantly (P < 0.05) higher neutrophil and lower lymphocyte counts. Serum glucose, total protein, albumin and total cholesterol levels were significantly (P < 0.05) lower in phthalate-exposed BB goats but higher the values of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and blood urea nitrogen (BUN) levels in treated BB goats. It may be concluded that exposure to a phthalate mixture during pregnancy alters the physical, hematological and biochemical parameters in BB goats.

Effects of varying doses of conjugated estrogen on body weight, hormonal and histological alterations of reproductive organs in adult swiss albino female mice.

Estrogens are a group of hormones that have diverse effects on both reproductive and non-reproductive organs. Conjugated estrogens are medicine that contains a mixture of estrogen hormones. The study was conducted to observe the effects of varying doses of conjugated estrogen on body weight, hormonal and histological alterations of reproductive organs in adult swiss albino female mice. In this study, 60 female swiss albino mice (Mus musculus) aged 28-30 days with an average body weight of 28.2 ± 1 g were used. At first, the mice were randomly divided into 4 groups each containing 15 mice. Group A was served as vehicle control and fed on standard mice pellet and fresh drinking water. While, groups B, C and D were administered with conjugated estrogen orally at the daily dose rate of 125 µg, 250 µg and 500 µg/kg body weight respectively with 1 mL sesame oil as a vehicle by mixing with feed. The experiment was carried out for 90 days. After humanly euthanized, blood was collected and serum was prepared and organs were collected for histopathology. The results revealed that higher doses of conjugated estrogen resulted in weight loss in premenopausal female mice compared to lower doses. Serum estrogen and thyroxine concentration was increased significantly following the doses of conjugated estrogen. Ovarian histotexture showed congested blood vessels and cystic space with degeneration of follicles and corpus luteum. Uterine lesions included massive macrophage infiltration in endometrium and hyperplasia of glandular epithelium at a lower dose; hyperplasia and hypertrophy of glandular epithelium (pleomorphism) with normal macrophage infiltration in endometrium at a higher dose. Therefore, it can be concluded that oral conjugated estrogen therapy at high dose has more detrimental impacts on body weight and reproductive function compared to lower dose in female adult mice.

Protective effects of cinnamon powder against hyperlipidemia and hepatotoxicity in butter fed female albino mice.

A butter-enriched high-fat diet changes lipid metabolism, resulting in fat storage, hyperlipidemia and obesity. Effects of cinnamon powder were investigated in butter-fed mice. 40 Swiss Albino mice, aged 28 to 30 days, were randomly assigned into two groups. Group A was an untreated control group (n = 8) and another group (n = 32) was a butter-treated group fed 10% butter. In the fifth week, mice of the butter-fed group were further divided into four equal groups: B, C, D, and E (n = 8), fed 10% butter with cinnamon 200 mg, 400 mg, and 600 mg powder per liter drinking water, respectively for 10 weeks. The butter-fed group was gained the most weight. Cinnamon supplementation significantly normalized weight gain and had no harmful effects on hematological parameters. Butter supplementation significantly increased total cholesterol (TC), triglycerides, and LDL cholesterol (LDL-c) whereas, cinnamon powder significantly reduced TC, LDL-c and glucose levels. In butter-fed mice, a significant increase was observed in the liver enzymes, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels with subsequent fat deposition in the liver. Excitingly, these enzymes were decreased and no fat depositions were observed in the liver of cinnamon-treated mice. Applying different concentrations of cinnamon powder improved the lipid profile in butter-fed female albino mice.

Promoting action of vitamin E and black seed oil on reproductive hormones and organ histoarchitecture of Swiss albino mice.

BACKGROUND: Vitamin E and black seed oil are two powerful antioxidants with several health benefits. OBJECTIVE: The effect of vitamin E and black seed oil on reproductive performance of Swiss albino mice was studied. METHODS: A total of 80 (40 male and 40 female) mice of 25-28 days old were randomly divided into four groups viz., A, B, C and D consisting of 10 mice in each group. Mice from the group A served as vehicle control and received normal mice ration whereas mice from the group B, C and D received feed supplemented with either black seed oil (0.5 ml/kg), vitamin E (200 mg/kg) or combination of black seed oil (0.5 ml/kg) and vitamin E (200 mg/kg), respectively daily for 16 weeks. At the end point of the study, blood samples were collected and sera were separated for hormonal analysis. At the same time, mice were sacrificed and testes and ovaries were collected for histomorphological examination. RESULTS: In male mice, the level of testosterone increased significantly in mice receiving black seed oil only, whereas the thyroxin increased significantly in all treated groups when compared to the control mice. Histomorphological examination revealed a significant increase in the diameter of seminiferous tubules in male mice fed with either black seed oil or vitamin E or both. On the other hand, the oestradiol and thyroxin concentration in female mice showed no significant changes in both control and treated groups. However, ovaries of mice fed with black seed oil or vitamin E or both showed an increased number of the follicles of different stages than the control mice. CONCLUSIONS: The findings highlighted the promoting action of vitamin E and black seed oil on reproductive functions of mice and that can be used to treat infertility in man and animals.

Retrieval action of zinc and folic acid for the restoration of normal reproductive function in bisphenol-A exposed male albino mice.

Bisphenol-A (BPA) has become a great concern due to its toxic effects. The present study investigated the retrieval action of zinc (Zn) and folic acid (FA) supplementation against BPA-induced reproductive toxicities in male albino mice. A total of seventy-five 25-28 day-old mice were divided into five equal groups (group A-E, 15 mice in each group). The mice were given normal rations (control, group A) or administered with daily doses of BPA at 50 mg/kg body weight (b.w.) (group B-E). The mice from groups C, D and E were supplemented with Zn (10 mg/kg b.w.), FA (3 mg/kg b.w.) and both in the feed, respectively, daily for 12 weeks. Blood samples were collected, and the sera were separated for biochemical and hormonal analyses. The standard method was followed to test the sperm motility and sperm count. The testis samples were processed for a routine histopathological study using haematoxylin and eosin staining. The sperm counts, motility, and serum testosterone significantly declined in the BPA-exposed animals, but dramatically increased after the Zn and FA supplementation. There was significant degeneration of the seminiferous tubules in the testes of the BPA-exposed mice, which was recovered moderately by the Zn and FA supplementation. The study shows the retrieval action of zinc and folic acid in the restoration of normal reproductive function in bisphenol-A exposed male mice.

Impacts of stocking density rates on welfare, growth, and hemato-biochemical profile in broiler chickens.

OBJECTIVE: The study investigated the effect of different stocking density (SD) rates on the welfare, growth, and hemato-biochemical parameters in broiler chickens. MATERIALS AND METHODS: 106 broiler chicks of 10 days old were used and assigned into four groups: A, B, C, and D. The chicks of group A were reared in floor space containing one bird per square foot area (SD1.0). The chicks of groups B, C, and D were reared at 1.5, 2.0, and 2.5 birds per square foot area (SD1.5, SD2.0, and SD2.5). Welfare, body weight, and hemato-biochemical parameters were assessed and monitored by physical observation and laboratory methods. RESULTS: The birds reared at SD2.0, and SD2.5 rates showed increased panting breathing. Wet feces adhered below the vent. There were a significant number of birds showing dirtiness of body and feathers. Birds reared in SD2.5 were familiar with moist litters and high ammonia smell. Foot-pad dermatitis, scratches, and blister formation were detected in the leg. The study revealed that the higher SD negatively correlated to the welfare behavior indicators. Live body weight was significantly (p < 0.05) decreased in birds reared at higher SD rates. Birds housed in SD1.0 and SD1.5 are optimum for body weight and improved feed conversion ratio. The hemato-biochemical parameters of birds reared at various SD rates did not differ. The total leucocyte count increased significantly, while total serum proteins decreased gradually as SD rates increased. CONCLUSION: This work explores that higher SD negatively affects welfare and growth performance in broiler chickens.

Flt3L-Mediated Expansion of Plasmacytoid Dendritic Cells Suppresses HIV Infection in Humanized Mice.

Plasmacytoid dendritic cells (plasmacytoid DC, pDC) are major IFN-I producers and have been shown to be affected by HIV through ill-defined mechanisms. In this study, we directly assess the role of pDC in early infection, evaluating whether modulating their abundance can alter viral replication. First, HIV infection of humanized mice induces systemic depletion of pDC, and in the presence of soluble FMS-like tyrosine kinase 3 ligand (Flt3L), pDC levels remain elevated. Flt3L significantly delays the onset of viremia and reduces viral replication via a process that is dependent on pDC and mediated through an enhanced early IFN-I response. pDC from Flt3L-treated mice are more prone to express IFN-α following TLR7 stimulation, but this propensity is gradually decreased during infection. In conclusion, maintaining pDC levels and function is key to effective early viral control, and in this context, these findings provide practical insights for anti-HIV strategies and vaccine design.

Conventional Dendritic Cells Impair Recovery after Myocardial Infarction.

Ischemic myocardial injury results in sterile cardiac inflammation that leads to tissue repair, two processes controlled by mononuclear phagocytes. Despite global burden of cardiovascular diseases, we do not understand the functional contribution to pathogenesis of specific cardiac mononuclear phagocyte lineages, in particular dendritic cells. To address this limitation, we used detailed lineage tracing and genetic studies to identify bona fide murine and human CD103+ conventional dendritic cell (cDC)1s, CD11b+ cDC2s, and plasmacytoid DCs (pDCs) in the heart of normal mice and immunocompromised NSG mice reconstituted with human CD34+ cells, respectively. After myocardial infarction (MI), the specific depletion of cDCs, but not pDCs, improved cardiac function and prevented adverse cardiac remodeling. Our results showed that fractional shortening measured after MI was not influenced by the absence of pDCs. Interestingly, however, depletion of cDCs significantly improved reduction in fractional shortening. Moreover, fibrosis and cell areas were reduced in infarcted zones. This correlated with reduced numbers of cardiac macrophages, neutrophils, and T cells, indicating a blunted inflammatory response. Accordingly, mRNA levels of proinflammatory cytokines IL-1ß and IFN-γ were reduced. Collectively, our results demonstrate the unequivocal pathological role of cDCs following MI.

Indoleamine 2,3-Dioxygenase-Expressing Aortic Plasmacytoid Dendritic Cells Protect against Atherosclerosis by Induction of Regulatory T Cells.

Plasmacytoid dendritic cells (pDCs) are unique bone-marrow-derived cells that produce large amounts of type I interferon in response to microbial stimulation. Furthermore, pDCs also promote T cell tolerance in sterile-inflammation conditions. However, the immunomodulatory role of aortic pDCs in atherosclerosis has been poorly understood. Here, we identified functional mouse and human pDCs in the aortic intima and showed that selective, inducible pDC depletion in mice exacerbates atherosclerosis. Aortic pDCs expressed CCR9 and indoleamine 2,3-dioxygenase 1 (IDO-1), an enzyme involved in driving the generation of regulatory T cells (Tregs). As a consequence, loss of pDCs resulted in decreased numbers of Tregs and reduced IL-10 levels in the aorta. Moreover, antigen presentation by pDCs expanded antigen-specific Tregs in the atherosclerotic aorta. Notably, Tregs ablation affected pDC homeostasis in diseased aorta. Accordingly, pDCs in human atherosclerotic aortas colocalized with Tregs. Collectively, we identified a mechanism of atheroprotection mediated by tolerogenic aortic pDCs.

Dab2, a negative regulator of DC immunogenicity, is an attractive molecular target for DC-based immunotherapy.

Dab2 is an adapter protein involved in receptor-mediated signaling, endocytosis, cell adhesion, hematopoietic cell differentiation, and angiogenesis. It plays a pivotal role in controlling cellular homeostasis. In the immune system, the Dab2 is a Foxp3 target gene and is required for regulatory T (Treg) cell function. Dab2 expression and its biological function in dendritic cells (DCs) have not been described. In this study, we found that Dab2 was significantly induced during the development of mouse bone marrow (BM)-derived DCs (BMDCs) and human monocyte-derived DCs (MoDCs). Even in a steady state, Dab2 was expressed in mouse splenic DCs (spDCs). STAT5 activation, Foxp3 expression, and hnRNPE1 activation mediated by PI3K/Akt signaling were required for Dab2 expression during GM-CSF-derived BMDC development regardless of TGF-ß signaling. Dab2-silencing was accompanied by enhanced IL-12 and IL-6 expression, and an improved capacity of DC for antigen uptake, migration and T cell stimulation, which generated strong CTL in vaccinated mice. Vaccination with Dab2-silenced DCs inhibited tumor growth more effectively than did vaccination with wild type DCs. Dab2-overexpression abrogated the efficacy of the DC vaccine in DC-based tumor immunotherapy. These data strongly suggest that Dab2 might be an intrinsic negative regulator of the immunogenicity of DCs, thus might be an attractive molecular target to improve DC vaccine efficacy.

Regulation of DC development and DC-mediated T-cell immunity via CISH.

Cytokine inducible SH2-containing protein (CISH) plays a crucial role in type 1 dendritic cell (DC) development as well as in the DC-mediated activation of cytotoxic T lymphocytes (CTLs). CISH expression at late DC developmental stages shuts down the proliferation of DC progenitors by negatively regulating signal transducer and activator of transcription 5 (STAT5) and facilitates the differentiation of DCs into potent stimulators of CTLs.

Egr2 induced during DC development acts as an intrinsic negative regulator of DC immunogenicity.

Early growth response gene 2 (Egr2), which encodes a zinc finger transcription factor, is rapidly and transiently induced in various cell types independently of de novo protein synthesis. Although a role for Egr2 is well established in T-cell development, Egr2 expression and its biological function in dendritic cells (DCs) have not yet been described. Here, we demonstrate Egr2 expression during DC development, and its role in DC-mediated immune responses. Egr2 is expressed in the later stage of DC development from BM precursor cells. Even at steady state, Egr2 is highly expressed in mouse splenic DCs. Egr2-knockdown (Egr2-KD) DCs showed increased levels of major histocompatability complex (MHC) class I and II and co-stimulatory molecules, and enhanced antigen uptake and migratory capacities. Furthermore, Egr2-KD abolished SOCS1 expression and signal transducer and activator of transcription 5 (STAT5) activation during DC development, probably resulting in the enhancement of IL-12 expression and Th1 immunogenicity of a DC vaccine. DC-mediated cytotoxic T lymphocyte (CTL) activation and antitumor immunity were significantly enhanced by Egr2-KD, and impaired by Egr2 overexpression in antigen-pulsed DC vaccines. These data suggest that Egr2 acts as an intrinsic negative regulator of DC immunogenicity and can be an attractive molecular target for DC vaccine development.

CISH is induced during DC development and regulates DC-mediated CTL activation.

The cytokine inducible SH2-domain protein (CISH) is a well-known STAT5 target gene, but its role in the immune system remains uncertain. In this study, we found that CISH is predominantly induced during dendritic cell (DC) development from mouse bone marrow (BM) cells and plays a crucial role in type 1 DC development and DC-mediated CTL activation. CISH knockdown reduced the expression of MHC class I, co-stimulatory molecules and pro-inflammatory cytokines in BMDCs. Meanwhile, the DC yield was markedly enhanced by CISH knockdown via cell-cycle activation and reduction of cell apoptosis. Down-regulation of cell proliferation at the later stage of DC development was found to be associated with CISH-mediated negative feedback regulation of STAT5 activation. In T-cell immunity, OT-1 T-cell proliferation was significantly reduced by CISH knockdown in DCs, whereas OT-2 T-cell proliferation was not affected by CISH knockdown. CTLs generated by DC vaccination were also markedly reduced by CISH knockdown, followed by significant impairment of DC-based tumor immunotherapy. Taken together, our data suggest that CISH expression at the later stage of DC development triggers the shutdown of DC progenitor cell proliferation and facilitates DC differentiation into a potent stimulator of CTLs.

New Cdc2 Tyr 4 phosphorylation by dsRNA-activated protein kinase triggers Cdc2 polyubiquitination and G2 arrest under genotoxic stresses.

Cell division cycle 2 (Cdc2) protein is an essential subunit of M-phase kinase (MPK), which has a key role in G2/M transition. Even though the control of MPK activity has been well established with regard to the phosphorylation of Cdc2 at Thr 14 and/or Tyr 15 and Thr 161, little is known about the proteolytic control of Cdc2. In this study, we observed that Cdc2 was downregulated under genotoxic stresses and that double-stranded RNA-activated protein kinase (PKR) was involved in the process. The PKR-mediated Tyr4 phosphorylation triggered Cdc2 ubiquitination. Phospho-mimic mutations at the Tyr 4 residue (Y4D or Y4E) caused significant ubiquitination of Cdc2 even in the absence of PKR. Our findings demonstrate that (i) PKR, Ser/Thr kinase, phosphorylates its new substrate Cdc2 at the Tyr 4 residue, (ii) PKR-mediated Tyr 4-phosphorylation facilitates Cdc2 ubiquitination and proteosomal degradation, (iii) unphosphorylated Tyr 4 prevents Cdc2 ubiquitination, and (iv) downstream from p53, PKR has a crucial role in G2 arrest and triggers Cdc2 downregulation under genotoxic conditions.