Physiological Roles of Hippo Signaling Pathway and Autophagy in Dementia

BACKGROUND

Dementia is a neurocognitive disorder associated with the aging brain and mainly affects the hippocampus and cerebral cortex. The Hippo signaling pathway and autophagy proteins have been found to be perturbed in the brain affected by dementia processes.

OBJECTIVE

This systematic review aims to elaborate on the involvement of the Hippo signaling pathway and autophagy in modulating the progression and severity of dementia in aging.

METHODS

Searches were conducted on MEDLINE, Google Scholar, Scopus, and Web of Science databases.

RESULTS

The Hippo signaling pathway is dependent upon the transcriptional co-activator YAP/TAZ, which forms complexes with TEAD in the nucleus in order to maintain cell homeostasis. When the expression YAP/TAZ is reduced, transcriptional repression-induced atypical cell death, ballooning cell death, and necrosis will consequently occur in the neurons. Moreover, the autophagic proteins, such as LC3, ATG proteins, and Beclin, are reduced, resulting in the disruption of autophagosome formation and accumulation and the spread of misfolded proteins in the brain suffering from dementia.

CONCLUSION

The impairment of the Hippo signaling pathway and autophagy in the dementia process in aging should be considered since it might predict the severity, treatment, and prevention of dementia. PROSPERO registration number CRD42022337445.

Recent Update on the Anti-Inflammatory Activities of Propolis

In recent years, research has demonstrated the efficacy propolis as a potential raw material for pharmaceuticals and nutraceuticals. There is limited report detailing the mechanisms of action of propolis and its bioactive compounds in relation to their anti-inflammatory properties. Thus, the aim of the present review is to examine the latest experimental evidence (2017-2022) regarding the anti-inflammatory properties of propolis. A systematic scoping review methodology was implemented. After applying the exclusion criteria, a total of 166 research publications were identified and retrieved from Scopus, Web of Science, and Pubmed. Several key themes related to the anti-inflammatory properties of propolis were subsequently identified, namely in relation to cancers, oral health, metabolic syndrome, organ toxicity and inflammation, immune system, wound healing, and pathogenic infections. Based on the latest experimental evidence, propolis is demonstrated to possess various mechanisms of action in modulating inflammation towards the regulatory balance and anti-inflammatory environment. In general, we summarize that propolis acts as an anti-inflammatory substance by inhibiting and downregulating TLR4, MyD88, IRAK4, TRIF, NLRP inflammasomes, NF-κB, and their associated pro-inflammatory cytokines such as IL-1β, IL-6, IFN-γ, and TNF-α. Propolis also reduces the migration of immune cells such as macrophages and neutrophils, possibly by downregulating the chemokines CXCL9 and CXCL10.

The Potential Use of Propolis as a Primary or an Adjunctive Therapy in Respiratory Tract-Related Diseases and Disorders: A Systematic Scoping Review

Propolis is a resinous beehive product that is collected by the bees from plant resin and exudates, to protect and maintain hive homeostasis. Propolis has been used by humans therapeutically to treat many ailments including respiratory tract-related diseases and disorders. The aim of the present systematic scoping review is to evaluate the experimental evidence to support the use of propolis as a primary or an adjunctive therapy in respiratory tract-related diseases and disorders. After applying the exclusion criteria, 158 research publications were retrieved and identified from Scopus, Web of Science, Pubmed, and Google Scholar. The key themes of the included studies were pathogenic infection-related diseases and disorders, inflammation-related disorders, lung cancers, and adverse effects. Furthermore, the potential molecular and biochemical mechanisms of action of propolis in alleviating respiratory tract-related diseases and disorders are discussed. In conclusion, the therapeutic benefits of propolis have been demonstrated by various in vitro studies, in silico studies, animal models, and human clinical trials. Based on the weight and robustness of the available experimental and clinical evidence, propolis is effective, either as a primary or an adjunctive therapy, in treating respiratory tract-related diseases.