Carnosol Reduced Pathogenic Protein Aggregation and Cognitive Impairment in Neurodegenerative Diseases Models via Improving Proteostasis and Ameliorating Mitochondrial Disorders

Rosmarinic acid ameliorated oxidative stress, neuronal injuries, and mitochondrial dysfunctions mediated by polyglutamine and ɑ-synuclein in Caenorhabditis elegans models

Numerous natural antioxidants have been developed into agents for neurodegenerative diseases (NDs) treatment. Rosmarinic acid (RA), an excellent antioxidant, exhibits neuroprotective activity, but its anti-NDs efficacy remains puzzling. Here, Caenorhabditis elegans models were employed to systematically reveal RA-mediated mechanisms in delaying NDs from diverse facets, including oxidative stress, the homeostasis of neural and protein, and mitochondrial disorders. Firstly, RA significantly inhibited reactive oxygen species accumulation, reduced peroxide malonaldehyde production, and strengthened the antioxidant defense system via increasing superoxide dismutase activity. Besides, RA reduced neuronal loss and ameliorated polyglutamine and ɑ-synuclein-mediated dyskinesia in NDs models. Further, in combination with the data and molecular docking results, RA may bind specifically to Huntington protein and ɑ-synuclein to prevent toxic protein aggregation and thus enhance proteostasis. Finally, RA ameliorated mitochondrial dysfunction including increasing adenosine triphosphate and mitochondrial membrane potential levels and rescuing mitochondrial membrane proteins' expressions and mitochondrial structural abnormalities via regulating mitochondrial dynamics genes and improving the mitochondrial kinetic homeostasis. Thus, this study systematically revealed the RA-mediated neuroprotective mechanism and promoted RA as a promising nutritional intervention strategy to prevent NDs.

Vanillin derivatives as antiamnesic agents in scopolamine-induced memory impairment in mice

Amnesia is a major health problem prevalent in almost every part of the world specifically in old age peoples. Vanillin analogues have played an important role in the field medicines. Some of them have been documented to be promising inhibitors of cholinesterases and could therefore, be used as antidepressant, anti-Alzheimer and as neuroprotective drugs. In this connection, the present study was designed to synthesize new vanillin analogues (SB-1 to SB-6) of varied biological potentials. The synthesized compounds were investigated as inhibitors against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes and as scavengers of DPPH and ABTS free radicals followed by behavioural antiamnesic evaluation in mice. The compounds; SB-1, SB-3, SB-4 and SB-6 more potently inhibited AChE with IC50 values of 0.078, 0.157, 0.108, and 0.014 μM respectively. The BChE was more potently inhibited by SB-3 with IC50 of 0.057 μM. Moreover, all of the tested compounds exhibited strong antioxidant potentials with promising results of SB-3 against DPPH with IC50 of 0.305 μM, while SB-5 was most active against ABTS with IC50 of 0.190 μM. The in-vivo studies revealed the improvement in memory deficit caused by scopolamine. Y-Maze and new object recognition test showed a considerable decline in cognitive dysfunctions. In Y-Maze test the spontaneous alteration of 69.44 ± 1% and 84.88 ± 1.35% for SB-1 and 68.92 ± 1% and 80.89 ± 1% for SB-3 at both test doses were recorded while during the novel object recognition test the Discrimination Index percentage of SB-1 was more pronounced as compared to standard drug. All compounds were found to be potent inhibitors of AChE, BChE, DPPH, and ABTS in vitro however, SB-1 and SB-3 were comparatively more potent. SB-1 was also more active in reclamation of memory deficit caused by scopolamine. SB-1 and SB-3 may be considered as excellent drug candidates for treating amnesia subjected to toxicological evaluations in other animal models.

Carnosol ameliorated cancer cachexia-associated myotube atrophy by targeting P5CS and its downstream pathways

Introduction: Carnosol exhibited ameliorating effects on muscle atrophy of mice developed cancer cachexia in our previous research. Method: Here, the ameliorating effects of carnosol on the C2C12 myotube atrophy result from simulated cancer cachexia injury, the conditioned medium of the C26 tumor cells or the LLC tumor cells, were observed. To clarify the mechanisms of carnosol, the possible direct target proteins of carnosol were searched using DARTS (drug affinity responsive target stability) assay and then confirmed using CETSA (cellular thermal shift assay). Furthermore, proteomic analysis was used to search its possible indirect target proteins by comparing the protein expression profiles of C2C12 myotubes under treatment of C26 medium, with or without the presence of carnosol. The signal network between the direct and indirect target proteins of carnosol was then constructed. Results: Our results showed that, Delta-1-pyrroline-5-carboxylate synthase (P5CS) might be the direct target protein of carnosol in myotubes. The influence of carnosol on amino acid metabolism downstream of P5CS was confirmed. Carnosol could upregulate the expression of proteins related to glutathione metabolism, anti-oxidant system, and heat shock response. Knockdown of P5CS could also ameliorate myotube atrophy and further enhance the ameliorating effects of carnosol. Discussion: These results suggested that carnosol might ameliorate cancer cachexia-associated myotube atrophy by targeting P5CS and its downstream pathways.

Chemical Profiling and Antioxidant and Anti-Amyloid Capacities of Salvia fruticosa Extracts from Greece

An increasingly common ailment in elderly persons is Alzheimer's disease (AD), a neurodegenerative illness. Present treatment is restricted to alleviating symptoms; hence, there is a requirement to develop an effective approach to AD treatment. Salvia fruticosa (SF) is a medicinal plant with a documented neuroprotective potential. To identify extracts of increased neuroprotectivity, we partitioned the methanolic extract of SF aerial parts from Greece into several fractions, by employing solvents of different polarities. The fractions were chemically identified and evaluated for their antioxidancy and anti-neurotoxic potential against amyloid beta peptides 25-35 (Aβ25-35). Carnosol and carnosic acid were among the prominent compounds, while all partitions showed significant antioxidant capacity, with the diethyl ether and ethyl acetate partitions being the most potent. These, along with the aqueous and the butanolic fractions, demonstrated statistically significant anti-neurotoxic potential. Thus, our findings further validate the neuroprotective potential of SF and support its ethnopharmacological usage as an antioxidant. The particular properties found define SF as a promising source for obtaining extracts or bioactive compounds, possibly beneficial for generating AD-related functional foods or medications. Finally, our results encourage plant extract partitioning for acquiring fractions of enhanced biological properties.

Four novel sleep-promoting peptides screened and identified from bovine casein hydrolysates using a patch-clamp model in vitro and Caenorhabditis elegans in vivo

Bovine casein hydrolysates (CHs) have demonstrated sleep-promoting activities. However, only few peptides were identified from CHs with sleep-promoting effects. In this work, an in vitro model based on the electrophysiology of brain neurons was established for the evaluation of sleep-promoting effects. Based on this model, four novel peptides were systematically separated from CH. Compared with the control group, the action potential (AP) inhibitory rate of four peptides increased by 38.63%, 340.93%, 233.28%, and 900%, respectively, and the membrane potential (MP) change rate of four peptides increased by 319.78%, 503.09%, 381.22%, and 547.10%, respectively. These results suggested that four peptides have sleep-promoting activities. Furthermore, Caenorhabditis elegans (C. elegans) sleep behavior results indicated that all the four peptides could significantly increase the total sleep duration, the motionless sleep duration of C. elegans, implying that these four peptides can significantly improve sleep. The LC-MS/MS results showed that the primary structures of these novel peptides were HQGLPQEVLNENLLR (α_s1-CN, f8-22), YKVPQLEIVPNSAEER (α_s1-CN, f104-119), HPIKHQGLPQEVLNENLLR (α_s1-CN, f4-22), and VPQLEIVPNSAEER (α_s1-CN, f106-119). Overall, this study revealed that the four novel sleep-promoting peptides identified were strong candidates as potential functional ingredients in the development of sleep-promoting products.