Assay for lipid peroxides in animal tissues by thiobarbituric acid reaction

Occurrence, Biogenesis, and Synthesis of Biologically Active Carbazole Alkaloids

Flavonoids and their glycosides, including anthocyanins

Excerpt Essentially all the hydroxyproline in the tissues of vertebrates is found in collagen, and, except for the small amount of hydroxyproline in elastin, no other animal protein contains signif...

Relationship of Hydroxyproline Excretion in Urine to Collagen Metabolism

Insulin resistance is a characteristic feature of obesity and type 2 diabetes mellitus and impacts the heart in various ways. Impaired insulin-mediated glucose uptake is a uniformly observed characteristic of the heart in these states, although changes in upstream kinase signaling are variable and dependent on the severity and duration of the associated obesity or diabetes mellitus. The understanding of the physiological and pathophysiological role of insulin resistance in the heart is evolving. To maintain its high energy demands, the heart is capable of using many metabolic substrates. Although insulin signaling may directly regulate cardiac metabolism, its main role is likely the regulation of substrate delivery from the periphery to the heart. In addition to promoting glucose uptake, insulin regulates long-chain fatty acid uptake, protein synthesis, and vascular function in the normal cardiovascular system. Recent advances in understanding the role of metabolic, signaling, and inflammatory pathways in obesity have provided opportunities to better understand the pathophysiology of insulin resistance in the heart. This review will summarize our current understanding of metabolic mechanisms for and consequences of insulin resistance in the heart and will discuss potential new areas for investigating novel mechanisms that contribute to insulin resistance in the heart.

Insulin Resistance: Metabolic Mechanisms and Consequences in the Heart

Antidiarrhoeal activity of carbazole alkaloids from Murraya koenigii Spreng (Rutaceae) seeds

Introduction: Recent periodicals direct that reactive carbonyl compounds are formed due to existing oxidative stress in type 2 diabetes mellitus, which further nonenzymatically react with proteins and lipids to form irreversible advanced glycation end products (AGE) and advanced lipoxidation end products (ALE). In type 2 diabetes mellitus, insulin resistance plays a pivotal role in hyperglycaemia. In this study, we tried to fi nd the relation between insulin resistance and carbonyl stress. Materials and Methods: Forty-seven patients of type 2 diabetes mellitus (age 51 ± 5.06 years) were selected and fasting plasma glucose, serum insulin, total carbonyl compounds, HbA1c, thiobarbituric acid reacting substances (TBARS) and Trolox equivalent antioxidant capacity (TEAC) were estimated using standard protocols. Homeostatic model assessement of insulin resistance (HOMA-IR) was evaluated from fasting plasma glucose and serum insulin levels. Results: We found highly signifi cant correlations of carbonyl compounds with HOMA-IR, fasting plasma glucose and glycated haemoglobin (HbA1c). Correlations of lipid peroxidation end product, TBARS were not so signifi cant. Conclusion: Findings from this study indicate that the level of carbonyl compounds can be a biomarker of insulin resistance in type 2 diabetes mellitus. Ann Acad Med Singapore 2010;39:909-12

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Elevated Level of Carbonyl Compounds Correlates with Insulin Resistance in Type 2 Diabetes

Malonato complexes of oxidovanadium(IV): Synthesis, structural characterization and exploration of their insulin mimetic properties

Introduction: Haemoglobin (Hb) E beta-thalassaemia is a common thalassaemic disorder in Southeast Asia and is very common in the eastern and north-eastern parts of India. The disease cause rapid erythrocyte destruction due to the free radical mediated injury but factors for the oxidative injury are not clearly known. We investigated the free reactive iron (non-haem) medi- ated insult in Hb E beta-thalassaemia. Materials and Methods: Thirty Hb E beta-thalassaemic patients (age range, 3 to 15 years) who had undergone blood transfusion at least 1 month prior to sampling and 32 normal healthy individuals (age range, 18 to 30 years) were included in this study. We estimated the ferrozine detected intracellular erythrocytic free reactive iron (non- haem iron), reduced glutathione (GSH), glutathione reductase activity, cellular damage marker serum thiobarbituric acid reacting substances (TBARS) and also serum ferritin using standard methods. Results: We found that the erythrocytic free reactive iron was signifi cantly higher (P <0.001) in Hb E beta patients and was about 30% more than in controls. The elevated level of erythrocytic non-haem iron was associated with a high level of serum TBARS which was about 86% higher in patients than in controls. The serum ferritin level was also signifi cantly higher (P <0.001) compared to controls. The erythrocytic reduced glutathione level was signifi cantly lower (P <0.001) at about 65% less in the patients' group and the erythrocytic glutathione re- ductase enzyme was also found to be signifi cantly lower (P <0.001) in Hb E beta-thalassaemia. Conclusions: We concluded that a signifi cantly elevated level of erythrocytic free reactive iron and lipid peroxidation end product was associated with low erythrocytic GSH level. This refl ects non-haem iron mediated cellular damage in Hb E beta-thalassaemia. Ann Acad Med Singapore 2010;39:13-6

/pdf/non-haem-iron-mediated-oxidative-stress-in-haemoglobin-e-4jjild1r4r.pdf

Non-haem iron-mediated oxidative stress in haemoglobin E beta-thalassaemia.

Pongamia pinnata is a plant known for its therapeutic usage in Indian traditional medicine. Despite the controversy regarding toxic flavonoid and erucic acid content, the seed of this plant is consumed in tribal medicine and its oil is used in Ayurveda to treat psoriasis and arthritis. This study explored the potential anti-arthritic effects of a P. pinnata seed (hexane) extract (PSE) at non-lethal doses in an adjuvant-induced arthritic rat model; possible mechanisms of any observed effects were also explored. After establishing the lethal doses arising from oral exposure to the extract, the material was administered per os daily at two doses (0.3 g/kg/day; 0.5 g/kg/day) to arthritic rats. Other rats received indomethacin or vehicle (control). Treatments were performed for a total of 14 days. One day after the final exposure, the rats were euthanized to permit harvest of various cells, blood, and tissues for analyses. Paw diameter and tissue myeloperoxidase activity in the paws were evaluated as i...

https://www.tandfonline.com/doi/pdf/10.3109/1547691X.2013.824931

Manoj Kar

Papers

Antidiarrhoeal activity of carbazole alkaloids from Murraya koenigii Spreng (Rutaceae) seeds

Elevated Level of Carbonyl Compounds Correlates with Insulin Resistance in Type 2 Diabetes

Malonato complexes of oxidovanadium(IV): Synthesis, structural characterization and exploration of their insulin mimetic properties

Non-haem iron-mediated oxidative stress in haemoglobin E beta-thalassaemia.

Suppression of NF-κB p65 nuclear translocation and tumor necrosis factor-α by Pongamia pinnata seed extract in adjuvant-induced arthritis.