Alzheimer's disease (AD) is a complex and progressive brain disorder marked by memory loss, cognitive decline, and behavioral changes. One of its defining features is the build-up of amyloid plaques, Show more
Alzheimer's disease (AD) is a complex and progressive brain disorder marked by memory loss, cognitive decline, and behavioral changes. One of its defining features is the build-up of amyloid plaques, clumps of β-amyloid (Aβ) peptides, in the brain, along with the formation of neurofibrillary tangles. These Aβ peptides are generated when the amyloid precursor protein (APP) is cleaved by enzymes, with β-secretase (BACE1) playing a key role in the first step of this process. Because BACE1 starts the cascade that leads to harmful Aβ build-up, it has become an important target in the search for effective Alzheimer's treatments. As Aβ accumulates in neurons, it disrupts communication between brain cells and triggers oxidative stress, which worsens damage and accelerates disease progression. This is often exacerbated by imbalances in metal ions, such as copper and iron. While tacrine, an early acetylcholinesterase inhibitor, has shown benefits in managing AD symptoms, its limitations have led researchers to explore improved versions. One promising direction is the development of tacrine-based hybrid molecules. By combining tacrine with other chemical groups that have anti-β-amyloid (Aβ) effects, antioxidant properties, and metal-chelating properties, scientists aim to create compounds that target multiple aspects of the disease simultaneously. This review examines the emerging potential of tacrine hybrids, particularly their capacity to inhibit BACE1 and prevent Aβ aggregation, providing new hope for more effective and disease-modifying therapies for Alzheimer's disease. Show less
Although numerous epidemiological studies have provided convincing evidence for an increase in the prevalence of colorectal cancer (CRC) in obese individuals, the precise mechanisms involved have not Show more
Although numerous epidemiological studies have provided convincing evidence for an increase in the prevalence of colorectal cancer (CRC) in obese individuals, the precise mechanisms involved have not been elucidated. Glucose-dependent insulinotropic polypeptide (GIP) is a gastrointestinal regulatory peptide whose primary physiologic role is to stimulate postprandial pancreatic insulin secretion. Like insulin, GIP has been linked to enhanced nutrient efficiency, which occurred during the course of evolution. Its expression is increased in obesity, and we thus initiated studies to examine whether GIP might contribute to the pathogenesis of obesity-related CRC. RT-PCR and Western analysis demonstrated the presence of the GIP receptor (GIPR) in several human CRC cell lines. GIP stimulated the proliferation of MC-26 cells, a mouse CRC cell line, in a concentration-dependent manner. Western analysis showed that GIP induced the activity of several downstream signaling molecules known to be involved in cellular proliferation in a concentration- and time-dependent manner. These studies indicate that the presence of GIP receptors in CRC may enable ligand binding and, in so doing, stimulate CRC cell proliferation. The overexpression of GIP, which occurs in obesity, might thereby be contributing to the enhanced rate of carcinogenesis observed in obesity. Show less