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Transforming growth factor (TGF)‐β signalling commences with the engagement of TGF‐β ligand to cell surface TGF‐β receptors (TGFBR) stimulating Smad2 carboxyl‐terminal phosphorylation (phospho‐Smad2C) and downstream biological responses. In several cell models, G protein‐coupled receptors (GPCRs) transactivate the TGF‐β receptors type‐1 (TGFBR1) leading to phospho‐Smad2C, however, we have recently published that in keratinocytes thrombin did not transactivate the TGFBR1. The bulk of TGFBRs reside in the cytosol and in response to protein kinase B (Akt phosphorylation) can translocate to the cell surface increasing the cell's responsiveness to TGF‐β. In this study, we investigate the role of Akt in GPCR transactivation of the TGFBR1. We demonstrate that angiotensin II and thrombin do not phosphorylate Smad2C in human vascular smooth muscle cells and in keratinocytes respectively. We used Akt agonist, SC79 to sensitise the cells to Akt and observed that Ang II and thrombin phosphorylate Smad2C via Akt/AS160‐dependent pathways. We show that SC79 rapidly translocates TGFBRs to the cell surface thus increasing the cell's response to the GPCR agonist. These findings highlight novel mechanistic insight for the role of Akt in GPCR transactivation of the TGFBR1. [ABSTRACT FROM AUTHOR]

Atherosclerosis, the major underlying pathology of cardiovascular disease, commences with the binding and trapping of lipids on modified proteoglycans, with hyperelongated glycosaminoglycan chains. Transforming growth factor (TGF)‐β stimulates glycosaminoglycan elongation in vascular smooth muscle cells. We have recently shown that this TGF‐β signaling pathway involves reactive oxygen species (ROS). YY‐11 is a dodecapeptide derived from camel milk and it has antioxidant activity. We have investigated the role of YY‐11 in blocking ROS signaling and downstream atherogenic responses. YY‐11 inhibited TGF‐β stimulated ROS production and inhibited the expression of genes for glycosaminoglycan chain elongation as a component of an in vitro model of atherosclerosis. This study provides a biochemical mechanism for the role of camel milk as a potential nutritional product to contribute to the worldwide amelioration of cardiovascular disease. Practical applications: The identification of readily accessible foods with antioxidant properties would provide a convenient and cost‐effective approach community wide reducing oxidative stress induced pathologies such as atherosclerosis. We demonstrate that camel milk‐derived peptide is an antioxidant that can inhibit growth factor‐mediated proteoglycan modification in vitro. As proteoglycan modification is being recognized as one of the earliest atherogenic responses, these data support the notion of camel milk as a suitable nutritional product to contribute to the prevention of early stage of atherosclerosis development. [ABSTRACT FROM AUTHOR]

We investigated the aqueous and ethanolic extracts of different forms (local names: mura and chora) of turmeric (Curcuma longa) from the Khulna and Chittagong divisions of Bangladesh for their antioxidant properties and polyphenol, flavonoid, tannin, and ascorbic acid contents. The antioxidant activity was determined using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radicalscavenging activity and ferric reducing antioxidant power (FRAP) values. The ethanolic extract of Chittagong's mura contained the highest concentrations of polyphenols (16.07%), flavonoids (9.66%), and ascorbic acid (0.09mg/100 g) and chora resulted in high yields (17.39%). The ethanolic extract of Khulna's mura showed a higher DPPH radical-scavenging activity with the lowest 50% inhibitory concentration (IC50) (1.08 κg/mL), while Khulna's chora had the highest FRAP value (4204.46 ± 74.48 M Fe [II] per 100 g). Overall, the ethanolic extract had higher antioxidant properties than those in the aqueous extract. However, the tannin concentration was lower in the ethanolic extract. We conclude that the turmeric varieties investigated in this study are useful sources of natural antioxidants, which confer significant protection against free radical damage. [ABSTRACT FROM AUTHOR]

Sundarban honey is one of the most renowned and popular types of honey from Bangladesh. This study was undertaken to investigate the antioxidant and DNA damage inhibition potentials of Sundarban honey. The estimated polyphenol, flavonoid, ascorbic acid, reducing sugar and protein contents in the investigated honey were found to be 593.96 ± 13.71 mg GAEs/kg, 50.00 ± 0.00 mg CEs/kg, 117.04 ± 1.05 mg/kg, 60.58 ± 3.23 g/100 g and 6.43 ± 0.12 mg/g, respectively. Some phenolics including gallic acid, pyrogallol, vanillic acid and trans-Cinnamic acid, as well as three flavonoids, naringin, rutin and quercetin, were identified and quantified by high performance liquid chromatography. Sundarban honey was found to possess protective activity against hydrogen peroxide and UV irradiation-induced damage to pBR322. The DNA protection activity of honey corresponded to its antioxidant potential and exhibited dose-dependent effects. Practical Application Sundarban honey, a wild multifloral honey produced by Apis dorsata bees is one of the most renowned types of honey from Bangladesh and confers protection against oxidative stress-induced liver and kidney damage. This honey can a be very good source of natural antioxidant which particularly contains some phenolic compounds including gallic, vanillic and trans-Cinnamic acids as well as three flavonoids (naringin, rutin and quercetin). Sundarban honey can protect against oxidative DNA damage and consecutive illness. [ABSTRACT FROM AUTHOR]

We investigated the protective role of Withania somnifera leaf extract (WSLEt) on isoproterenol- (ISO-) induced myocardial infarction (MI) in rats. Subcutaneous injection of ISO (85 mg/kg body weight (b.w.)) administered to rats for two consecutive days caused a significant increase in cardiac troponin I (cTnI) levels and serum lipid profiles, as well as the activities of some marker enzymes. In addition to these diagnostic markers, there were increased levels of lipid peroxidation (LPO) and decreased activities of enzymatic antioxidants (superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GRx), and glutathione-S-transferase (GST)) in the myocardium. However, oral pretreatment (100 mg/kg b.w.) with WSLEt for 4 weeks elicited a significant cardioprotective activity by lowering the levels of cTnI, lipid profiles, and marker enzymes. The levels of LPO products were also significantly decreased. Elevated activities of antioxidant enzymes were also observed in rats pretreated with WSLEt. As further confirmed histopathologically, our findings strongly suggest that the cardioprotective effect of WSLEt on myocardium experiencing ISO-induced oxidative damage may be due to an augmentation of the endogenous antioxidant system and an inhibition of LPO in the myocardial membrane. We conclude that WSLEt confers some protection against oxidative damage in ISO-induced MI in rats. [ABSTRACT FROM AUTHOR]

BAU Kul ( Z iziphus mauritiana) is a new and improved variety of plum fruit from Bangladesh. This study aims to investigate the antioxidant potency and antibacterial activity of methanolic extracts of BAU Kul using Soxhlet extraction followed by complete evaporation of residual methanol. BAU Kul is a very good source of phenolics, flavonoids, ascorbic acid and tannins. The reducing sugar and protein content of BAU Kul were 1.68 and 0.81% by weight, respectively. BAU Kul was very active in 1,1-diphenyl-2- picrylhydrazyl radical (DPPH) scavenging and ferric reducing antioxidant power assay (527.28 ± 9.2 [μ M Fe ( II)]/100 g), thus confirming its high antioxidant potential. Antibacterial activities were measured using the agar well-diffusion method. BAU Kul was most toxic to P seudomonas aeruginosa, followed (in order) by S taphylococcus aureus, S almonella paratyphi, E scherichia coli and C hromobacterium violaceum. In conclusion, BAU Kul is a nutritious fruit that provides good antioxidant and antibacterial activities (in particular toward P . aeruginosa) and a cheap source of vitamins. Practical Applications BAU Kul is a new and sweet seasonal fruit which is very popular to the consumers of Bangladesh. This fruit can be a good source of nutrients as well as the antioxidants applicable in different types of diseases caused by oxidative stresses. BAU Kul can also be used as traditional medicine for different types for infectious diseases. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to investigate the antioxidant and antimicrobial activities of a methanolic extract of Apple kul ( Z izyphus mauritiana) as it has not been studied extensively. Apple kul was found to be a rich source of polyphenols (52.19 ± 2.38 mg gallic acid equivalents/100 g), flavonoids (13.19 ± 1.31 mg catechin equivalents/100 g), ascorbic acid (48.17 ± 2.04 mg ascorbate equivalent/100 g) and tannins (50.20 ± 3.61 mg tannic acid equivalents/100 g). The estimated protein and reducing sugar contents in Apple kul were 1.21 ± 0.04 g/100 g and 1.96 ± 0.15 g/100 g, respectively. The high ferric-reducing antioxidant power value (6336.71 ± 554.88 μmol Fe [ II]/g) also indicated a high antioxidant potency for Apple kul. Apple kul showed highest activity towards P seudomonas aeruginosa and S taphylococcus aureus. Practical Applications Apple kul is full of vital potential antioxidants and can act as an antimicrobial agent, which is beneficial to fight against oxidative stress associated diseases as well as against harmful bacteria to maintain a healthy human life. [ABSTRACT FROM AUTHOR]