A conglomeration of preclinical models related to myocardial infarction

Cardiovascular diseases are the main source of death and morbidity in developed and developing nations. Animal models are required to propel our understanding of the pathogenesis, increase our knowledge, disease progress, and mechanism behind cardiovascular disorder, providing new approaches focused to improve the diagnostic and the treatment of these pathological conditions and additionally to test various therapeutic ways to deal with tissue regeneration and re-establish heart working following damage. A perfect model framework ought to be reasonable, effectively controlled, reproducible, and physiologically illustrative of human disease, show cardinal signs and pathology that resembles after the human ailment and ethically stable. The decision of selection of animal model should be considered precisely since it influences exploratory results and whether results of the research can be sensibly matched with the human. In this way, no specific technique splendidly reproduces the human disease, and relying upon the model, extra cost burden, resources, infrastructure and the necessity for technical hands, should also be kept under consideration. Here we have discussed and compiled various methods of inducing myocardial infarction in animals, basically by surgery, chemicals and through genetic modification, this may benefit the researchers in getting a complied data regarding various methods through which they can induce myocardial infarction in animals.

Wound healing potential of flowers extracts of Woodfordia fruticosa Kurz.

Wound healing or repair is the body’s natural process of regenerating dermal and epidermal tissue. Woodfordia fruticosa Kurz (Family: Lythraceae) is used traditionally in wound healing by the tribals of Chhattisgarh district. However, there is a paucity of scientific data in support. In this study, we evaluated antimicrobial activity of petroleum ether, chloroform, ethanolic and aqueous extracts against a diverse range of gram +ve and gram -ve bacteria along with pathogenic fungi. The wound healing activity of ethanolic extract was also evaluated at dose levels of 250 and 500 mg/kg body wt in rats by excision, incision and dead space wound healing models along with histopathology of wound area of skin. The ethanolic extract showed potent wound healing activity, as evident from the increase in the wound contraction and breaking strength in dose-dependent manner. Treatment with ethanolic extract (250 and 500 mg/kg body wt) showed significant dose-dependently decrease in epithelization period and scar area. Hydroxyproline, hexuronic acid and hexosamine contents, the important constituents of extracellular matrix of healing were also correlated with the observed healing pattern. During early wound healing phase, pro-inflammatory cytokines TNF-α, IL-6 and anti-inflammatory cytokine IL-10 levels were found to be upregulated by the ethanolic extract treatment. The ethanolic extract exhibited a strong and broad spectrum antimicrobial activity, as compared to other extracts. It showed very low Minimum inhibitory concentration (MIC) values and inhibited the growth of E. coli, Staphylococcus aureus and Candida albicans in concentration of 2.5 µg/disc. Thus, the results of the present study demonstrated the strong wound healing potential and antimicrobial activities of W. fruticosa, flowers, supporting the folklore use of the plant by the tribal people of Chhattisgarh district.

Pharmacological evaluation of hyperin for antihyperglycemic activity and effect on lipid profile in diabetic rats.

Antihyperglycemic potential of hyperin at 25 and 50 mg/kg doses for 30 days to streptozotocin induced diabetic rats has been reported. In oral glucose tolerance test, hyperin treated rats showed a significant reduction in blood glucose level after 120 min. It was found that hyperin exhibited dose dependent and significant antihyperglycemic activity in streptozotocin induced diabetic rats which were nearly similar with standard drug glybenclamide. Activities of glucose-6-phosphatase, fructose-1,6-bisphosphatase, glycogen phosphorylase, glycosylated haemoglobin and level of serum urea and creatinine were significantly decreased in hyperin supplemented diabetic rats, dose dependently. Activities of hexokinase and glycogen synthase were increased with augmentation in liver glycogen, insulin and haemoglobin content in hyperin treated diabetic rats. General hematological parameters did not show any significant change in hyperin treated diabetic rats hence it is safe at these doses. Histopathological studies showed significant morphological changes in pancreatic β-cells of streptozotocin induced diabetic rats. A decreased number of secretory granules of β- cells were observed in diabetic rats and these pathological abnormalities were normalized after treatment with hyperin and standard drug glybenclamide. Further, hyperin decreases significant in serum total cholesterol, triglyceride, low density lipoprotein, very low density lipoprotein levels coupled with elevation of high density lipoprotein in diabetic rats. These results suggest that hyperin has a pivotal role in blood glucose level in streptozotocin induced hyperglycemia by improving the function of pancreatic islets and increasing glycolysis and decreasing gluconeogenesis.

Antihyperglycemic activity of Woodfordia fruticosa (Kurz) flowers extracts in glucose metabolism and lipid peroxidation in streptozotocin-induced diabetic rats.

The ethanolic extract of W. fruticosa flowers (250 and 500 mg/kg) significantly reduced fasting blood glucose level and increased insulin level after 21 days treatment in streptozotocin diabetic rats. The extract also increased catalase, superoxide dismutase, glutathione reductase, glutathione peroxidase activities significantly and reduced lipid peroxidation. Glycolytic enzymes showed a significant increase in their levels while a significant decrease was observed in the levels of the gluconeogenic enzymes in ethanolic extract treated diabetic rats. The extract has a favourable effect on the histopathological changes of the pancreatic β- cells in streptozotocin induced diabetic rats. The results suggest that W. fruticosa possess potential antihyperglycemic effect by regulating glucose homeostasis and antioxidant efficacy in streptozotocin-induced diabetic rats.

Coat protein sequence shows that Cucumber mosaic virus isolate from geraniums (Pelargonium spp.) belongs to subgroup II.

A viral disease was identified on geraniums (Pelargonium spp.) grown in a greenhouse at the Institute of Himalayan Bioresource Technology (IHBT), Palampur, exhibiting mild mottling and stunting. The causal virus (Cucumber mosaic virus, CMV) was identified and characterized on the basis of host range, aphid transmission, enzyme linked immunosorbent assay (ELISA), DNA-RNA hybridization and reverse transcription polymerase chain reaction (RT-PCR). A complete coat protein (CP) gene was amplified using degenerate primers and sequenced. The CP gene showed nucleotide and amino acid homology up to 97%-98% and 96%-99%, respectively with the sequences of CMV subgroup II. The CP gene also showed homologies of 75%-97% in nucleotide and 77%-96% in amino acid with the CMV Indian isolates infecting various crops. On the basis of sequence homology, it was concluded that CMV-infecting geraniums in India belong to subgroup II.