Md. Ashraful Alam

Xanthine Oxidase Inhibitor, Allopurinol, Prevented Oxidative Stress, Fibrosis, and Myocardial Damage in Isoproterenol Induced Aged Rats

We evaluated the preventive effect of allopurinol on isoproterenol (ISO) induced myocardial infarction in aged rats. Twelve- to fourteen-month-old male Long Evans rats were divided into three groups: control, ISO, and ISO + allopurinol. At the end of the study, all rats were sacrificed for blood and organ sample collection to evaluate biochemical parameters and oxidative stress markers analyses. Histopathological examinations were also conducted to assess inflammatory cell infiltration and fibrosis in heart and kidneys. Our investigation revealed that the levels of oxidative stress markers were significantly increased while the level of cellular antioxidants, catalase activity, and glutathione concentration in ISO induced rats decreased. Treatment with allopurinol to ISO induced rats prevented the elevated activities of AST, ALT, and ALP enzymes, and the levels of lipid peroxidation products and increased reduced glutathione concentration. ISO induced rats also showed massive inflammatory cells infiltration and fibrosis in heart and kidneys. Furthermore, allopurinol treatment prevented the inflammatory cells infiltration and fibrosis in ISO induced rats. In conclusion, the results of our study suggest that allopurinol treatment is capable of protecting heart of ISO induced myocardial infarction in rats probably by preventing oxidative stress, inflammation, and fibrosis.

Tadalafil enhances working memory, and reduces hippocampal oxidative stress in both young and aged mice

Tadalafil, a type-5 phosphodiesterase enzyme inhibitor with long half-life used to treat erectile dysfunction. Recently it has been reported that tadalafil improves cognitive function. Here, we aimed to investigate the age dependent effects of tadalafil on memory, locomotor, behavior, and oxidative stress in the hippocampus. Tadalafil was orally administered everyday (5 mg/kg) to young (2 months) and old (16 months) healthy mice for 4 weeks. Control mice from each group received equal volume of 0.9% normal saline for the same duration. Memory and locomotor activity were tested using radial arm maze and open field test respectively. The level of malondialdehyde (MDA), nitric oxide (NO), and advanced protein oxidation product (APOP) was analyzed and catalase activity was determined from the isolated hippocampus. Treatment with tadalafil in aged mice improves working memory than the corresponding tadalafil treated young mice in radial arm maze test. Tadalafil treated mice traveled less distance in the center and the mean speed of tadalafil treated aged mice was significantly lower than the tadalafil treated young mice in open field test. Tadalafil treatment elicited a decrease of MDA level in the hippocampus of aged mice than that of young mice. APOP level was decreased only in aged mice treated with tadalafil. Treatment with tadalafil decreased NO and increased catalase activity in both young and aged mice. On the basis of previous and our findings, we conclude that tadalafil treatment reduces oxidative stress while increased cGMP level in the hippocampus might be responsible for memory enhancement.

Astaxanthin Prevented Oxidative Stress in Heart and Kidneys of Isoproterenol-Administered Aged Rats

ABSTRACT The objective of this study was to investigate the effect of astaxanthin on isoproterenol (ISO)-induced myocardial infarction and cardiac hypertrophy in rats. To evaluate the effect of astaxanthin on ISO-induced cardiac dysfunction, 18 aged Long Evans male rats were evenly divided into three groups. Group I (Control group) was given only the laboratory-ground food and normal water. Group II (ISO group) was administered ISO at a dose of 50 mg/kg subcutaneously (SC) twice a week for two weeks. Group III (Astaxanthin + ISO group) was treated with astaxanthin (25 mg/kg) orally every day and ISO 50 mg/kg SC twice a week for two weeks. ISO administration in rats increased the heart and left ventricular wet weights and increased inflammatory cell infiltration and fibrosis. Moreover, ISO administration increased the lipid peroxidation and decreased antioxidant enzyme activities in heart tissues. Astaxanthin treatment prevented the increased wet weight of heart and decreased inflammatory cell infiltration and fibrosis. The protective effect of astaxanthin was associated with reduction of free radicals by improving antioxidant enzyme function, as well as normalization and/or suppression of elevated oxidative stress markers, such as malondialdehyde (MDA), nitric oxide (NO), and advanced protein oxidation product (APOP) in ISO-administered rats. Furthermore, astaxanthin decreased the elevated activities of aspartate transaminase (AST), alanine transaminase (ALT), and creatinin kinase muscle/brain (CK-MB) in ISO-administered rats. In conclusion, astaxanthin may protect cardiac tissues in ISO-administered rats through suppression of oxidative stress and enhancement of antioxidant enzyme functions.

Functionalized hBN as targeted photothermal chemotherapy for complete eradication of cancer cells

The development of combined anticancer therapeutic techniques has drawn increased attention for enhanced therapeutic efficacy. In this work, we synthesized Near Infrared (NIR) responsive ICG (I) functionalized hexagonal boron-nitride (hBN) as photothermal therapeutic agent (hBNI) and Doxorubicin (Dox)-conjugated Hyaluronic acid (HA) as tumor targeted chemotherapeutic agent (d-HA-Dox). Using adhesion properties of Dopamine (d), the hBNI has been integrated with d-HA-Dox to make a tumor targeted photothermal chemotherapeutic agent (hBNI/d-HA-Dox). The nanostructure of hBNI/d-HA-Dox has been studied using 1H NMR, FTIR, UV-vis-NIR and AFM images. Our in vitro results have provided evidence that hBNI/d-HA-Dox can efficiently damage targeted cancer cells while healthy cells are less affected suggesting that the targeted hBNI/d-HA-Dox nanoparticles work as a complementary antitumor agent with its synergistic co-therapeutic power.

Astaxanthin ameliorates hepatic damage and oxidative stress in carbon tetrachloride-administered rats

Background: Astaxanthin is of carotenoids group which possess strong antioxidant properties. The present study was conducted to evaluate the hepatoprotective effects of astaxanthin in carbon tetrachloride (CCl4)-treated rats. Materials and Methods: Female Long-Evans rats were administered with CCl4 orally (1 ml/kg) twice a week for 2 weeks and were treated with astaxanthin (10 mg/kg) every day for 2 weeks. Blood plasma samples were isolated from each group and were analyzed for alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase activities. Oxidative stress parameters such as malondialdehyde (MDA), nitric oxide (NO), and advanced protein oxidation product (APOP) were measured. Several enzyme functions such as myeloperoxidase (MPO), superoxide dismutase (SOD), and catalase (CAT) activities in the plasma and liver tissues were also analyzed. Moreover, inflammation and tissue fibrosis were also confirmed by histological staining of liver tissues. Results: This investigation revealed that CCl4 administration in rats increased plasma AST, ALT, and ALP activities which were normalized by astaxanthin treatment. Moreover, CCl4 administration increased as MDA, NO, and APOP level both in plasma and tissues compared to control rats. Astaxanthin also exhibited a significant reduction of those parameters in CCl4-administered rats. Astaxanthin treatment also restored the CAT and SOD activities and lowered MPO activity in CCl4-administered rats. Histological assessment also revealed that the astaxanthin prevented the inflammatory cells infiltration, decreased free iron deposition, and fibrosis in liver of CCl4-administered rats. Conclusion: These results suggest that astaxanthin protects liver damage induced by CCl4 by inhibiting lipid peroxidation and stimulating the cellular antioxidant system.

Cardioprotective effect of Amaranthus tricolor extract in isoprenaline induced myocardial damage in ovariectomized rats

Red spinach (Amaranthus tricolor) has been reported to possess many benefits and medicinal properties and used as a part of traditional medicine in Ayurveda and Siddha. The aim of the study was to investigate the effects of Amaranthus tricolor on isoproterenol-induced oxidative stress, fibrosis, and myocardial damage in ovariectomized rats. Ovariectomy surgery was conducted to remove both ovaries from the rats. After recovery, rats were administered with ISO subcutaneously (50 mg/kg) twice a week and were treated with ethanolic extracts of A. tricolor. This investigation showed that the level of oxidative stress markers was significantly increased while the superoxide dismutase (SOD) activity decreased in ISO administered ovariectomized rats. A. tricolor extract and atenolol treatment prevented the rise of malondialdehyde, nitric oxide and advanced protein oxidation product. Moreover, elevated activities of AST, ALT, and CK-MB enzymes were also lowered by both atenolol and A. tricolor treatment. Increased uric acid and creatinine levels were also normalized by atenolol, and A. Tricolor treatment in ISO administered ovariectomized rats. ISO-induced ovariectomized rats also showed massive inflammatory cell infiltration, fibrosis and iron deposition in heart compared to sham rats. Atenolol and A. tricolor treatment prevented the inflammatory cells infiltration, fibrosis, and iron deposition. These results suggest that A. tricolor treatment may protect against ISO administered myocardial infarction in ovariectomized rats probably by preventing inflammation, oxidative stress, and fibrosis. Further research is warranted to examine molecular mechanism of cardioprotective effect of A. tricolor.

The Advances and Applications of Arynes and Their Precursors to Synthesize the Heterocyclic Compounds: A Review

The aryne and its intermediates or their precursors are the most important compounds in organic synthesis for the purpose of arynes or benzyne insertion in many reactions. Arynes are among the first reactive intermediates known to organic chemists. Since their discovery, they have fascinated chemists from both theoretical and synthetic perspectives. These remarkable intermediates possess a wide reactivity profile, engaging in the different types of reactions especially in organic chemistry fields like nucleophilic addition reactions, pericyclic reactions, [4+2] and [3+2] cycloaddition reactions and transition metal-mediated/catalyzed reactions. This methodology would also be applicable for the synthesis of biologically and pharmaceutically active products such as isocoumarins, benzodiazepines and other important compounds in one pot reactions.

Antinociceptive and Anti-Inflammatory Activities of Mycetia longifolia (Wall.) O. Kuntze

Mycetia longifolia is used traditionally for the treatment of pain, inflammation, ulcers, and wounds. Phytochemical analysis revealed the presence of alkaloids, flavonoids, tannins, glycosides, and polyphenols. The ethanol extract of the plant was investigated for its antinociceptive and anti-inflammatory activities in mice models and compared to the reference drug diclofenac sodium and control. In the acetic acid-induced writhing model, the extract showed a good antinociceptive effect characterized by the reduction in the number of writhes. The percent inhibition of writhing response by the extract was 74.56% at 500 mg.kg−1 dose. The extract caused decrease in licking time and licking frequency in mice when placed on a hot plate. The extract at doses of 250 and 500 mg.kg−1 b.w. inhibited the formation of paw edema induced by carrageenan.