Artemisia alleviates AGE-induced liver complications via MAPK and RAGE signaling pathways modulation: a combinatorial study

Protective impacts of Artemisia annua against hepatic toxicity induced by gentamicin

The current study aimed to investigate the ameliorative effects of Artemisia annua (RA) extract on hepatic toxicity induced by gentamicin injection mice. Sixteen mice were divided into four groups; the control group received saline, the second group received 1% A. annua (RA) extract, third group injected 80 mg/kg gentamicin (GEN) intraperitoneally. The protective group treated with a combination of GEN and A. annua. All mice were treated for consecutive 15 days. Results confirmed that hepatic biomarkers (GPT, GCT, GOT, IL-6 and IL-1β), all were altered after gentamycin injection. The histological analysis confirmed that gentamycin injected mice showed portal vein congestion, micro and macro steatosis, and nuclear pyknosis of hepatocytes. The protective group showed intact central vein with less microsteatosis of some hepatocytes. Immunochemistry analysis confirmed that the immunoreactivity of COX-2 gene showed negative impact in examined groups. Unlike, NF-κB gene exhibited diffuse positive expression in the gentamicin group. TGF-β1 immunoreactivity was mild positive in control and highly upregulated in gentamicin treated mice, all were normalized after RA administration. In conclusion, RA showed a beneficial impact against gentamycin induced hepatic toxicity at cellular and biochemical levels by regulating proteins and inflammatory markers associated with liver activity.

RAGE Inhibitors in Neurodegenerative Diseases

Nonenzymatic reactions of reducing sugars with primary amino groups of amino acids, proteins, and nucleic acids, followed by oxidative degradations would lead to the formation of advanced glycation endproducts (AGEs). The AGEs exert multifactorial effects on cell damage leading to the onset of neurological disorders. The interaction of AGEs with the receptors for advanced glycation endproducts (RAGE) contribute to the activation of intracellular signaling and the expression of the pro-inflammatory transcription factors and various inflammatory cytokines. This inflammatory signaling cascade is associated with various neurological diseases, including Alzheimer's disease (AD), secondary effects of traumatic brain injury (TBI), amyotrophic lateral sclerosis (ALS), and diabetic neuropathy, and other AGE-related diseases, including diabetes and atherosclerosis. Furthermore, the imbalance of gut microbiota and intestinal inflammation are also associated with endothelial dysfunction, disrupted blood-brain barrier (BBB) and thereby the onset and progression of AD and other neurological diseases. AGEs and RAGE play an important role in altering the gut microbiota composition and thereby increase the gut permeability and affect the modulation of the immune-related cytokines. The inhibition of the AGE-RAGE interactions, through small molecule-based therapeutics, prevents the inflammatory cascade of events associated with AGE-RAGE interactions, and thereby attenuates the disease progression. Some of the RAGE antagonists, such as Azeliragon, are currently in clinical development for treating neurological diseases, including AD, although currently there have been no FDA-approved therapeutics based on the RAGE antagonists. This review outlines the AGE-RAGE interactions as a leading cause of the onset of neurological diseases and the current efforts on developing therapeutics for neurological diseases based on the RAGE antagonists.