Balvinder K. Manuja

Sodium alginate and gum acacia hydrogels of ZnO nanoparticles show wound healing effect on fibroblast cells

An ideal biomaterial for wound dressing applications should possess antibacterial and anti-inflammatory properties without any toxicity to the host cells while providing the maximum healing activity. Zinc oxide nanoparticles (ZnONPs) possess antimicrobial activity and enhance wound healing, but the questions regarding their safety arise before application to the biological systems. We synthesized ZnONPs-loaded-sodium alginate-gum acacia hydrogels (SAGA-ZnONPs) by cross linking hydroxyl groups of the polymers sodium alginate and gum acacia with the aldehyde group of gluteradehyde. Here, we report the wound healing properties of sodium alginate/gum acacia/ZnONPs, circumventing the toxicity of ZnONPs simultaneously. We demonstrated the concentration-dependent zones of inhibition in treated cultures of Pseudomonas aerigunosa and Bacillus cereus and biocompatability on peripheral blood mononuclear/fibroblast cells. SAGA-ZnONPs hydrogels showed a healing effect at a low concentration of ZnONPs using sheep fibroblast cells. Our findings suggest that high concentrations of ZnONPs were toxic to cells but SAGA-ZnONPs hydrogels significantly reduced the toxicity and preserved the beneficial antibacterial and healing effect.

Quinapyramine sulfate-loaded sodium alginate nanoparticles show enhanced trypanocidal activity

AIM To reduce the dose, toxic effects and to ensure sustained release of quinapyramine sulfate (QS), a highly effective drug against Trypanosoma evansi. MATERIALS & METHODS QS-loaded sodium alginate nanoparticles (QS-NPs) were formed by emulsion-crosslinking technology using dioctyl-sodium-sulfosuccinate and sodium alginate. The formulation was characterized for size, stability, morphology and functional groups by a zetasizer, scanning electron microscopy, atomic force microscopy, transmission electron microscopy and Fourier transform infrared spectroscopy. In vitro safety and toxicity studies were performed by metabolic assay in Vero cell lines, and in vivo efficacy was evaluated in mice. RESULTS QS-NPs were <60 nm with 96.48% entrapment efficiency and 3.70% drug loading. The formulation showed an initial burst effect followed by slow drug release in accordance with quasi-Fickian Higuchi diffusion mechanism. QS-NPs were much less toxic and able to clear the parasite at a much lower concentration than QS. CONCLUSION The QS-NPs synthesized are safe, less toxic and highly effective compared with QS.

A novel genomic constellation (G10P[3]) of group A rotavirus detected from buffalo calves in northern India

Group A bovine rotaviruses cause gastroenteritis and calf mortality leading to significant economic losses to dairy farmers in India. Due to segmented nature of the RNA genome and wide host range, vast genetic and antigenic diversity exists among different isolates of rotavirus. Molecular characterization of locally prevalent group A rotavirus strains in buffalo population in north India was undertaken. Out of a total of 455 faecal samples, 21 samples (4.61%) were positive for bovine rota virus (BRV) as determined by PAGE and ELISA, whereas of these only 15 isolates yielded specific products for VP4 and VP7 genes by RT-PCR. Genotyping by nested PCR typed G6, G10 and P[11] genotypes but VP4 genes of 11 isolates remained untyped. The phylogenetic and evolutionary analysis of nucleotide and predicted amino acid sequences of the cloned products of VP4 and VP7 genes confirmed typing results obtained by nested PCR for G6, G10 and P[11] and classified the untyped isolates as P[3] genotypes. In this study, it was observed that G6P[11] (26.66%) and G10P[3] (73.34%) group A rotaviruses are circulating in buffalo herds of organized farms in north India. Unusual reassortants G10P[3] of group A rotaviruses isolated from buffalo calves show novel genomic constellations indicative of interspecies reassortment.

Zinc Oxide Nanoparticles: Opportunities and Challenges in Veterinary Sciences

Nanotechnology has opened up new vistas for applications in almost all the disciplines of veterinary and animal sciences. Zinc oxide (ZnO) has been used as an alternative to antibiotics in animal feed. It has also been widely used for wound healing and various skin disorders. Recently ZnO nanoparticles (NPs) have attracted attention owing to their unique features. There can be numerous applications of ZnO NPs due to their antibacterial, antineoplastic, wound healing, ultraviolet scattering and angiogenic properties. These have also been used to promote tissue repair, as a food preservative and as feed additive. This paper reviews the recent developments in ZnO NPs research and its potential for application in animal health and production.

Immunotherapeutic potential of CpG oligodeoxynucleotides in veterinary species

Abstract Innate immunity plays a critical role in host defense against infectious diseases by discriminating between self and infectious non-self. The recognition of infectious non-self involves germ-line encoded pattern recognition receptors (PRRs) that recognize pathogen-associated molecular patterns (PAMPs). The PAMPs are the components of pathogenic microbes which include not only the cell wall constituents but also the unmethylated 2′-deoxy-ribo-cytosine-phosphate-guanosine (CpG) motifs. These CpG motifs present within bacterial and viral DNA are recognized by toll-like receptor 9 (TLR9), and signaling by this receptor triggers a proinflammatory cytokine response which, in turn, influences both innate and adaptive immune responses. The activation of TLR9 with synthetic CpG oligodeoxynucleotides (ODNs) induces powerful Th1-like immune responses. It has been shown to provide protection against infectious diseases, allergy and cancer in laboratory animal models and some domestic animal species. With better understanding of the basic biology and immune mechanisms, it would be possible to exploit the potential of CpG motifs for animal welfare. The research developments in the area of CpG and TLR9 and the potential applications in animal health have been reviewed in this article.

Sodium alginate and gum acacia hydrogels of zinc oxide nanoparticles reduce hemolytic and oxidative stress inflicted by zinc oxide nanoparticles on mammalian cells

Zinc oxide nanoparticles are important nanomaterials currently under research due to their applicability in nanomedicine. Toxicity of ZnO NPs has been extensively studied and has been shown to affect various cell types and animal systems. In this study, we investigated hemolytic potential and oxidative stress inflicted by ZnO NPs and ZnO NPs-loaded-sodium alginate-gum acacia hydrogels on horse erythrocytes and African green monkey kidney (Vero) cells. Our study provides a better understanding of the hemolytic and oxidative effects of interaction of ZnO NPs and ZnO NPs released from polymeric hydrogels with the biological system. Remarkable aggregation of erythrocytes was noted in the higher concentration of ZnO NPs treated erythrocytes as compared to erythrocytes treated with ZnO NPs-loaded hydrogels. ZnO NPs-loaded hydrogels treated Vero cells significantly reduced oxidative stress as evidenced by less malondialdehyde production as compared to that of ZnO NPs treated cells. Normal horse erythrocytes when treated with ZnO NPs in in vitro condition undergo oxidative damage, and contribute in augmenting the toxicity. We demonstrated that polymeric ZnO NPs reduced the undesirable effects provoked by ZnO NPs on mammalian cells.

Chemotherapeutic Approaches Against Trypanosoma evansi: Retrospective Analysis, Current Status and Future Outlook

Trypanosoma evansi, the causative agent of surra, is pathogenic to a wide variety of wild and domestic animals, including equines, camels, goats, sheep, cattle, buffaloes, pigs, dogs, tigers, elephants etc. The infection is mainly restricted to animals but ability to infect human beings has also been reported due to the lack of efficient apolipoprotein L 1. The parasite is mechanically transmitted by blood-sucking flies such as Tabanus and Stomoxys species. The disease has a major economic impact in tropical countries. The control of trypanosomosis may be aimed either at the fly or against the parasite. Due to difficulties in large scale fly control, trypanocides have been widely used to control the disease. However, current chemotherapeutic agents are limited in number and usually associated with severe side effects. Moreover, current therapeutic agents are far from ideal. The emergence of drug resistant trypanosomes results in failure of prophylaxis and treatment of the disease. Retrospective and prospective studies on drug and delivery against T. evansi will provide an overview of the chemotherapeutic and prophylactic measures in vogue and suggest future strategies for combating this neglected disease. In this perspective, we have reviewed the currently used drugs available for prophylaxis and therapy, their mechanism of action and associated limitations. The options available for prophylaxis and therapy along with potential new molecules/therapeutic agents and novel approaches for delivery of the drugs to enhance their therapeutic value are presented in this review.

CpG-ODN Class C Mediated Immunostimulation in Rabbit Model of Trypanosoma evansi Infection

CpG oligodeoxynucleotides (CpG-ODN) stimulate immune cells from a wide spectrum of mammalian species. Class C CpG-ODN is relatively stable and has the combined immune effects of both A and B classes of CpG-ODN. Trypanosoma evansi produces the state of immuno-suppression in the infected hosts. The current chemotherapeutic agents against this parasite are limited in number and usually associated with severe side effects. The present work aimed to determine the immunostimulatory effects of CpG-ODN class C in T. evansi infected rabbits. Rabbits inoculated with CpG C and challenged with T. evansi resulted in delayed onset of clinical signs with reduced severity in comparison to that of T. evansi infected rabbits. The treatment also enhanced humoral immune responses. Histopathological findings in liver and spleen revealed enhancement of mononuclear cell infiltration and secondary B cell follicles. These results demonstrate that CpG-ODN class C, has immunostimulatory properties in rabbit model of trypanosomosis. The use of booster doses or sustained delivery of CpG-ODN will further elucidate the prolonged CpG-ODN generated immune responses.

Comparative Analysis of Molecular Structure, Function and Expression of Buffalo (Bubalus bubalis) Toll-Like Receptor 9

Toll-like receptor 9 (TLR9) has been characterized as a receptor that recognizes unmethylated CpG motif and triggers a pro-inflammatory cytokine response that influences both innate and adaptive immunity. Buffalo is an economically important livestock species in many Asian and Mediterranean countries, but there is little information available on its TLR9 structure and response to stimulation with its agonist CpG-ODNs. Hence in this study, we report the analysis of newly sequenced buffalo TLR9 gene fragment. In this study, buffalo TLR9 amino acid sequence revealed close association of TLR9 proteins within other bovines and small ruminants; but high divergence from other species. Multiple alignment of deduced amino acid sequence of Bubalus bubalis TLR9 with other species showed that 156/201 (74.28%) amino acids were conserved in all species. Leucine rich repeat (LRR) motifs in the ectodomain of TLR9 are responsible for molecular recognition of its agonist. The LRR pattern of Bubalus bubalis TLR9 protein was predicted towards N-terminal sequence and was found to be conserved among all species except Rattus norvegicus and Equus caballus. Blast analysis of buffalo TLR9 sequence with single nucleotide polymorphisms (SNPs) database revealed 13 SNPs out of which 7 were cds-synonymous and 6 were of the functional significance. Furthermore, kinetics of TLR9 and proinflammatory IL-1β and TNF-α cytokine expression by buffalo PBMCs influenced by CpG-ODN is also discussed.

Synthesis and evaluation of isometamidium-alginate nanoparticles on equine mononuclear and red blood cells

Isometamidium hydrochloride (ISMM) is an effective drug for the treatment of trypanosomosis, but it causes local and systemic toxicity. Isometamidium hydrochloride has limited therapeutic index and exhibit considerable variation in their prophylactic activities. We developed a trypanocidal nanoformulation using ISMM and polymers sodium alginate/gum acacia to enhance the efficacy of the drug at lower doses, while minimizing undesirable side effects. It was characterized by transmission electron microscopy and infrared spectroscopy for evaluation of size, morphology, functional groups, etc. In vitro cytotoxicity studies were performed by metabolic resazurin assay at different concentrations of isometamidium-loaded alginate/gum acacia nanoparticles using equine peripheral blood mononuclear cells. Hemolytic assay revealed significantly less toxicity compared to the conventional drug. The results demonstrate that the developed drug delivery module can be evaluated in suitable animal models to evaluate its potency.