TGF-β Signaling: A Therapeutic Target to Reinstate Regenerative Plasticity in Vascular Dementia?

Berberine Improves Cognitive Impairment by Simultaneously Impacting Cerebral Blood Flow and β-Amyloid Accumulation in an APP/tau/PS1 Mouse Model of Alzheimer's Disease

Alzheimer's disease (AD) is accompanied by β-amyloid (Aβ), neurofibrillary tangles, and neuron cell death, and is one of the most commonly occurring diseases among the elderly. The pathology of AD is complex, involving Aβ overproduction and accumulation, tau hyperphosphorylation, and neuronal loss. In addition, chronic cerebral hypoperfusion (CCH) is ubiquitous in the AD patients and plans a pivotal role in triggering and exacerbating the pathophysiological progress of AD. The goal of this study was to investigate the neuroprotective properties of berberine (BBR) and the underlying mechanism. During the study, BBR was administrated to treat the triple-transgenic mouse model of Alzheimer's disease (3×Tg AD). To thoroughly evaluate the effects of the BBR administration, multiple manners were utilized, for instance, 3D arterial spin labeling technique, Morris water maze assay, immunofluorescence staining, TUNEL assay, laser speckle contrast imaging, western blotting, etc. The results showed that BBR ameliorated cognitive deficits in 3×Tg AD mice, reduced the Aβ accumulation, inhibited the apoptosis of neurons, promoted the formation of microvessels in the mouse brain by enhancing brain CD31, VEGF, N-cadherin, Ang-1. The new vessels promoted by BBR were observed to have a complete structure and perfect function, which in turn promoted the recovery of cerebral blood flow (CBF). In general, berberine is effective to 3×Tg AD mice, has a neuroprotective effect, and is a candidate drug for the multi-target prevention and treatment of AD.

Network and 16S rRNA Sequencing-Combined Approach Provides Insightal Evidence of Vitamin K2 for Salt-Sensitive Hypertension

Vitamin K₂ (VK2), found to act to treat hypertension, has been widely used in the food and pharmaceutical industries nowadays. However, the potential targets and molecular mechanisms of VK2 for salt-sensitive hypertension have not been fully investigated. Therefore, the study aimed to investigate the potential molecular mechanisms of VK2 for salt-sensitive hypertension using network pharmacology and 16S rRNA sequencing strategy. The network pharmacology-based findings from KEGG enrichment analysis revealed that VK2-treated salt-sensitive hypertension was mechanically associated with the complement and coagulation cascades, calcium signaling pathway, renin–angiotensin system, etc. A total of 29 different bacteria in an animal experiment after VK2 supplementation were screened and functionally enriched using PICRUSt2. Additionally, 10 signaling pathways were identified in which the renin–angiotensin system was found to be the potential molecular mechanisms with the greatest change in multiple and statistical significance. Moreover, the results of the renin–angiotensin system-related protein expression exhibited VK2-inhibited renin–angiotensin system in salt-induced hypertensive mice, which significantly verified the previous biological and functional prediction analysis. Finally, spearman correlation analysis showed the different bacteria such as Dubosiella, Ileibacterium, etc., had a positive or negative correlation with renin–angiotensin system-related proteins in salt-induced mice. In conclusion, the potential molecular mechanisms of VK2 for salt-sensitive hypertension may be beneficially achieved by the specific inhibition of the renin–angiotensin system, contributing to the development for a new preventive strategy of salt-sensitive hypertension.

Pathological changes in neurovascular units: Lessons from cases of vascular dementia

Vascular dementia (VD) is the second leading cause of dementia after Alzheimer's disease (AD). The decrease of cerebral blood flow (CBF) to different degrees is one of the main causes of VD. Neurovascular unit (NVU) is a vessel‐centered concept, emphasizing all the cellular components play an integrated role in maintaining the normal physiological functions of the brain. More and more evidence shows that reduced CBF causes a series of changes in NVU, such as impaired neuronal function, abnormal activation of glial cells, and changes in vascular permeability, all of which collectively play a role in the pathogenesis of VD. In this paper, we review NVU changes as CBF decreases, focusing on each cellular component of NVU. We also highlight remote ischemic preconditioning as a promising approach for VD prevention and treatment from the NVU perspective of view.

Intramuscular Injection of BOTOX® Boosts Learning and Memory in Adult Mice in Association with Enriched Circulation of Platelets and Enhanced Density of Pyramidal Neurons in the Hippocampus

BOTOX® is a therapeutic form of botulinum neurotoxin. It acts by blocking the release of acetylcholine (ACh) from the synaptic vesicles at the neuromuscular junctions, thereby inhibiting the muscle contraction. Notably, many neurological diseases have been characterized by movement disorders in association with abnormal levels of ACh. Thus, blockade of aberrant release of ACh appears to be a potential therapeutic strategy to mitigate many neurological deficits. BOTOX® has widely been used to manage a number of clinical complications like neuromuscular disorders, migraine and neuropathic pain. While the beneficial effects of BOTOX® against movement disorders have extensively been studied, its possible role in the outcome of cognitive function remains to be determined. Therefore, we investigated the effect of BOTOX® on learning and memory in experimental adult mice using behavioural paradigms such as open field task, Morris water maze and novel object recognition test in correlation with haematological parameters and histological assessments of the brain. Results revealed that a mild dose of BOTOX® treatment via an intramuscular route in adult animals improves learning and memory in association with increased number of circulating platelets and enhanced structural plasticity in the hippocampus. In the future, this minimally invasive treatment could be implemented to ameliorate different forms of dementia resulting from abnormal ageing and various neurocognitive disorders including Alzheimer's disease (AD).

Therapeutic effect of TRC105 and decitabine combination in AML xenografts

Acute myeloid leukemia (AML) is an aggressive hematologic malignancy, often characterized by poor prognosis following standard induction therapy. The hypomethylating agent decitabine (DAC) is an alternative treatment for elderly and relapsed/refractory AML patients, yet responses following DAC monotherapy are still modest. The transforming growth factor-β (TGF-β) receptor CD105 (endoglin) is expressed in various hematopoietic malignancies, and high CD105 expression correlates with poor prognosis in AML patients. Using a xenograft model, we have recently demonstrated that targeting CD105⁺ AML blasts with the TRC105 monoclonal antibody inhibits leukemia progression. Here we investigated whether administration of TRC105 along with DAC could represent a novel therapeutic option for relapsed/refractory AML. Our data show that the DAC/TRC105 combination results in a more durable anti-leukemic effect in AML xenografts compared to DAC monotherapy. Moreover, the DAC/TRC105 combination enhanced reactive oxygen species (ROS) activity, which correlated with reduced leukemia burden. RNA-sequencing studies suggest that TRC105 may alter TGF-β activity in AML blasts. Taken together, these findings provide rationale for the clinical evaluation of TRC105 in combination with DAC in AML patients.