Antibacterial effect is one of the major therapeutic activities of plant-derived Curcumin. This work evaluated the effect of serum albumin, human plasma, and whole blood on the in vitro activity of Curcumin against eight clinical bacterial isolates by standard broth microdilution and plate-counting methods. Toxicological effects of Curcumin towards human red blood cells (RBCs) and peripheral blood mononuclear cells (PBMCs) were also investigated. Curcumin exhibited weak activity against gram-negative bacteria, except Escherichia coli and Shigella flexneri were susceptible and was most active against gram-positive bacteria: Staphylococcus aureus, Streptococcus pyogenes and Enterococcus faecalis. The antibacterial activity was impaired in the presence of bovine serum albumin (BSA), human plasma and whole blood. Curcumin was not toxic to PBMCs and RBCs at 200μg/mL. Furthermore, Curcumin showed synergistic activity in combination with antibiotics: Ciprofloxacin, Gentamicin, Vancomycin and Amikacin against Staphylococcus aureus. This study demonstrated that the interaction of Curcumin with plasma proteins diminishes its in vitro antibacterial activity. Curcumin derivatives with reduced affinity for plasma protein may improve the bioavailability and antibacterial activities.
Neurodegenerative disease is an incurable disease which involves the degeneration or death of the nerve cells. Alzheimer's Disease (AD) is a neurodegenerative disease discovered in 1906 by Alois Alzheimer, a German clinical psychiatrist and neuroanatomist. The main pathological hallmarks of this disease are the formation of extracellular amyloid β (Aβ) plaques and intracellular neurofibrillary tangle (NFT). The accumulation of the amyloid protein aggregates in the brain of AD patients leads to oxidative stress and inflammation. Other postulated reasons for the development of this disease are cholinergic depletion and excessive glutamatergic neurotransmission. The current drugs approved and marketed for the treatment of AD are cholinesterase inhibitors (ChEIs) and N-methyl-Daspartate (NMDA) receptor antagonists. The function of ChEIs is to avoid cholinergic depletion; whereas the function of NMDA receptor antagonist is to block excessive glutamatergic neurotransmission. Unfortunately, the current drugs prescribed for AD show only modest improvement in terms of symptomatic relief and delay the progression of the disease. This review will discuss about several polyphenolic compounds as potential natural treatment options for AD. Three compounds are highlighted in this review - Curcumin (Cur), Resveratrol (Rsv) and Epigallocatechin-3- gallate (EGCG). These compounds have huge potential for AD treatment, especially due to their low frequency of adverse events. However, the current conventional pharmaceutical drugs remain as the mainstay of treatment for AD.
Lung cancer is among the most common cancers with a high mortality rate worldwide. Despite the significant advances in diagnostic and therapeutic approaches, lung cancer prognoses and survival rates remain poor due to late diagnosis, drug resistance, and adverse effects. Therefore, new intervention therapies, such as the use of natural compounds with decreased toxicities, have been considered in lung cancer therapy. Curcumin, a natural occurring polyphenol derived from turmeric (Curcuma longa) has been studied extensively in recent years for its therapeutic effects. It has been shown that curcumin demonstrates anti-cancer effects in lung cancer through various mechanisms, including inhibition of cell proliferation, invasion, and metastasis, induction of apoptosis, epigenetic alterations, and regulation of microRNA expression. Several invitro and invivo studies have shown that these mechanisms are modulated by multiple molecular targets such as STAT3, EGFR, FOXO3a, TGF-β, eIF2α, COX-2, Bcl-2, PI3KAkt/mTOR, ROS, Fas/FasL, Cdc42, E-cadherin, MMPs, and adiponectin. In addition, limitations, strategies to overcome curcumin bioavailability, and potential side effects as well as clinical trials were also reviewed.