Exploring multifunctional antioxidants as potential agents for management of neurological disorders

Free radical or oxidative stress may be a fundamental mechanism underlying several human neurologic diseases. Therapy using free radical scavengers (antioxidants) has the potential to prevent, delay, or ameliorate many neurologic disorders. However, the biochemistry of oxidative pathobiology is complex, and optimum antioxidant therapeutic options may vary and need to be tailored to individual diseases. In vitro and animal model studies support the potential beneficial role of various antioxidant compounds in neurological disease. Antioxidants generally play an important role in reducing or preventing the cell damage and other changes which occur in the cells like mitochondrial dysfunction, DNA mutations, and lipid peroxidation in the cell membrane. Based on their mechanism of action, antioxidants can be used to treat various neurological disorders like Huntington's disease, Alzheimer's disease, and Parkinson's disease. Vitamin E has a scavenging action for reactive oxygen species (ROS) and also prevents the lipid peroxidation. Creatine generally reduces the mitochondrial dysfunction in Parkinson's disease (PD) patients. Various metal chelators are used in PD for the prevention of accumulation of the metals. Superoxidase dismutase (SOD), lipases, and proteases act as repair enzymes in patients with AD. Accordingly, the antioxidant defense system is found to be most useful for treating various neurological disorders.

Purification of novel angiotensin converting enzyme inhibitory peptides from beef myofibrillar proteins and analysis of their effect in spontaneously hypertensive rat model

This study was conducted to purify the angiotensin converting enzyme (ACE) inhibitory peptides from beef myofibrillar proteins by using inexpensive enzymes alkaline-AK and papain. Different molecular weight peptides (<3 and <10 kDa) were obtained using ultrafiltration. The <3 kDa peptides obtained by alkaline-AK (AK3K) digestion showed the highest ACE inhibitory activity (74.29%) as compared to other alkaline-AK peptides, and a strong antihypertensive effect of AK3K was observed in the spontaneously hypertensive rat (SHR) model. The AK3K treatment groups (400 and 800 mg/kg body weight) exhibited a decrease in systolic blood pressure (SBP) by 28 and 35 mmHg, respectively in the SHR model. The study demonstrated that the ACE inhibitory peptide obtained from beef myofibrillar proteins had the sequence Leu-Ile-Val-Gly-Ile-Ile-Arg-Cys-Val, and could be possibly used for lowering the SBP.

Effects of selenium on oxidative damage and antioxidant enzymes of eukaryotic cells: wine Saccharomyces cerevisiae

AIM

To clarify the effects of selenium (Se), parameters related to oxidative issues, as well as the antioxidant response were investigated on an autochthonous wine yeast strain.

METHODS AND RESULTS

Antioxidant enzyme activity, gel electrophoresis, Western blot and MDA level were used to investigate the effects of different concentration of Se in wine yeast. We found that Se is able to affect the enzymatic activities of catalase (CAT), glutathione peroxidase (GPx) and superoxide dismutase (SOD). An increase in lipid peroxidation was observed in a dose-dependent manner of (Se), thus, indicating the occurrence of cell membrane damage. Additionally, Se induced post-translational oxidative modifications of proteins, especially oxidation of thiol groups (both reversible and irreversible) and protein carbonylation (irreversible oxidation).

CONCLUSION

These results obtained could further the understanding the effect of different concentration of Se in wine yeast strain with which Se affect the enzymatic activities and induces some post-translational modifications of proteins.

SIGNIFICANCE AND IMPACT OF THE STUDY

The understanding of mechanisms regulating the response of wine yeast to Se is important for future work using selenized yeast as enriched Se supplements in human nutrition.

Nigella sativa and Its Protective Role in Oxidative Stress and Hypertension

Hypertension increases the risk for a variety of cardiovascular diseases, including stroke, coronary artery disease, heart failure, and peripheral vascular disease. The increase in oxidative stress has been associated with the pathogenesis of hypertension. Increase of blood pressure is due to an imbalance between antioxidants defence mechanisms and free radical productions. Excessive production of reactive oxygen species reduces nitric oxide bioavailability leading to an endothelial dysfunction and a subsequent increase in total peripheral resistance. Hypertension can cause few symptoms until it reaches the advanced stage and poses serious health problems with lifelong consequences. Hypertensive patients are required to take drugs for life to control the hypertension and prevent complications. Some of these drugs are expensive and may have adverse reactions. Hence, it is timely to examine scientifically, complimentary therapies that are more effective and with minimal undesirable effects. Nigella sativa (NS) and its active constituents have been documented to exhibit antioxidant, hypotensive, calcium channel blockade and diuretic properties which may contribute to reduce blood pressure. This suggests a potential role of NS in the management of hypertension, and thus more studies should be conducted to evaluate its effectiveness.