Curcumin and Its Derivatives as Theranostic Agents in Alzheimer’s Disease: The Implication of Nanotechnology

Abstract

Curcumin is a polyphenolic natural compound with diverse and attractive biological properties, which may prevent or ameliorate pathological processes underlying age-related cognitive decline, Alzheimer’s disease (AD), dementia, or mode disorders. AD is a chronic neurodegenerative disorder that is known as one of the rapidly growing diseases, especially in the elderly population. Moreover, being the eminent cause of dementia, posing problems for families, societies as well a severe burden on the economy. There are no effective drugs to cure AD. Although curcumin and its derivatives have shown properties that can be considered useful in inhibiting the hallmarks of AD, however, they have low bioavailability. Furthermore, to combat diagnostic and therapeutic limitations, various nanoformulations have also been recognized as theranostic agents that can also enhance the pharmacokinetic properties of curcumin and other bioactive compounds. Nanocarriers have shown beneficial properties to deliver curcumin and other nutritional compounds against the blood-brain barrier to efficiently distribute them in the brain. This review spotlights the role and effectiveness of curcumin and its derivatives in AD. Besides, the gut metabolism of curcumin and the effects of nanoparticles and their possible activity as diagnostic and therapeutic agents in AD also discussed.

Crosstalk between Gut and Brain in Alzheimer’s Disease: The Role of Gut Microbiota Modulation Strategies

“…Among different kinds of dementia, AD is the most common [55], and it contributes to 60-80% of dementia cases [56]. It is one of the rapidly growing brain diseases [13] and it has been reported that AD and other types of dementia represent the 5th most prominent reason for deaths around the globe. Around 50 million people suffer from dementia, and this is expected to double by 2030, and triple by 2050.…”

“…Different epidemiological studies suggest a strong correlation among lifestyle-related factors, diet, and the onset and consolidation of AD and other kinds of dementia [13]. Studies have reported that nutritional interventions might be helpful to mitigate or delay the risk of cognitive impairment, AD and other non-psychiatric comorbidities.…”

“…Polyphenols (PPs) are naturally occurring bioactive compounds and the most abundant forms of antioxidants in the human diet [63]. PPs have been recognized as potent agents that can lower the risk of AD [13]. Furthermore, vitamins have a positive effect on AD due to their role in preventing oxidative stress and inflammation that would otherwise lead to Aβ and tau phosphorylation [108,109].…”

“…Alterations of the GM community are referred to as dysbiosis [4,10], and these can lead to metabolic disorders. However, recent studies have proposed that this can also affect the central nervous system (CNS) because of the microbiota-gut-brain axis (MGBX) [11][12][13]. The brain regulates the secretory and sensory functions of the gut, and the connection between the gut and brain is interceded by physiological channels such as the autonomic nervous system, neuroendocrine system, neuroimmune pathways, and signaling molecules produced by the GM [14].…”

Curcumin and Its Potential Impact on Microbiota

“…In addition it exerts antioxidant and anti-inflammatory properties. It may have many therapeutic effects [2,3], having exhibited antitumor, chemosensitizing, hepatoprotective, lipid-modifying, and neuroprotective effects [4]. Nevertheless, wellreported in vivo pharmacological activities of curcumin are limited by its poor solubility, bioavailability, and pharmacokinetic profile.…”