Inhibition of protease-activated receptor 1 (PAR1) ameliorates cognitive performance and synaptic plasticity impairments in animal model of Alzheimer's diseases

Myrtenol Inhalation Mitigates Asthma-Induced Cognitive Impairments: an Electrophysiological, Behavioral, Histological, and Molecular Study

Asthma is an inflammatory disorder with significant health problems. It generally affects the lungs but can also impact brain performance via several mechanisms. Some investigations have proposed that asthma impairs cognition. This study assessed the impacts of myrtenol as a monoterpene on cognitive disorders following asthma at behavioral, molecular, and synaptic levels. Asthma was induced by injection and inhalation of ovalbumin (OVA). Male Wistar rats were allocated to five groups: control, asthma, asthma/vehicle, asthma/myrtenol, and asthma/budesonide. Myrtenol (8 mg/kg) or budesonide (160 μg/kg) was administered through inhalation once a day for 1 week, and at the end of the inhalation period, behavioral tests (MWM and Open Field), field potential recording, hippocampal brain-derived neurotrophic factor (BDNF), IL1β (ELISA), and NFκB measurement (Western blot) were performed to evaluate cognitive performance. Moreover, H&E (hematoxylin and eosin) staining was used for hippocampus histological evaluation. Myrtenol improved spatial learning, memory, LTP (long-term potentiation) impairments, and anxiety-like behaviors following asthma. Myrtenol inhalation increased the BDNF level and decreased the IL1β level and NFκB expression in the hippocampus of the asthmatic rats. The neuronal damage in the hippocampus following allergic asthma was alleviated via myrtenol administration. Myrtenol, as an herbal extract, protects the hippocampus from asthma consequences. Our observations revealed that myrtenol can improve spatial learning, memory, synaptic plasticity impairments, and anxiety-like behaviors following asthma. We believe that these ameliorating effects of myrtenol can be attributed to inflammation suppression and increased BDNF in the hippocampus.

Ameliorating effects of Acacia arabica and Ocimum basilicum on acetic acid-induced ulcerative colitis model through mitigation of inflammation and oxidative stress

Introduction

Ulcerative colitis (UC) is a chronic recurrent inflammatory disease of the large intestine and rectum. The disease is characterized by oxidative stress and severe inflammation. Research has shown the anti-oxidative and anti-inflammatory effects induced by consuming the Acacia arabia and Ocimum basilicum. The present study aimed to evaluate the effect of treatment with O. basilicum together with A. arabica on healing, inflammation, and oxidative stress in the course of experimental colitis in rats.

Methods

A total number of 50 male rats were selected and randomly assigned to five groups of 10 rats each. Colitis was induced in rats by enemas with a 4 % acetic acid solution. Four days after the colitis induction, the rats were orally treated for the next 4 days with saline or a combination of A. arabica and O. basilicum (1000 mg/kg) or sulfasalazine (100 mg/kg).

Results

Acetic acid-induced colitis increased the colon's macroscopic and histopathological damage scores; increased colon levels of MDA (Malondialdehyde), MPO (Myeloperoxidase), TNF-α (Tissue necrosis factor α), IL6 (Interleukin 6), and IL17 (Interleukin 17); and decreased SOD (Superoxide Dismutase), GPx (Glutathione Peroxidase), and IL10 (Interleukin 10) levels in the treated rats compared with the control group (P < 0.001). Overall, a combination of A. arabica and O. basilicum reduced macroscopic and histopathological damage scores (P < 0.01) of the colon, and MDA, MPO, TNF-α, IL6 (P < 0.001), and IL17 (P < 0.01) levels of the colon. Furthermore, it increased SOD, GPx, and IL10 levels compared to the colitis group (P < 0.01).

Conclusion

A. arabica and O. basilicum have improving effects on UC by reducing inflammation and oxidative stress.

Antiplatelet drugs: Potential therapeutic options for the management of neurodegenerative diseases

The blood platelet plays an important role but often remains under-recognized in several vascular complications and associated diseases. Surprisingly, platelet hyperactivity and hyperaggregability have often been considered the critical risk factors for developing vascular dysfunctions in several neurodegenerative diseases (NDDs) like Alzheimer's disease, Parkinson's disease, Huntington's disease, and multiple sclerosis. In addition, platelet structural and functional impairments promote prothrombotic and proinflammatory environment that can aggravate the progression of several NDDs. These findings provide the rationale for using antiplatelet agents not only to prevent morbidity but also to reduce mortality caused by NDDs. Therefore, we thoroughly review the evidence supporting the potential pleiotropic effects of several novel classes of synthetic antiplatelet drugs, that is, cyclooxygenase inhibitors, adenosine diphosphate receptor antagonists, protease-activated receptor blockers, and glycoprotein IIb/IIIa receptor inhibitors in NDDs. Apart from this, the review also emphasizes the recent developments of selected natural antiplatelet phytochemicals belonging to key classes of plant-based bioactive compounds, including polyphenols, alkaloids, terpenoids, and flavonoids as potential therapeutic candidates in NDDs. We believe that the broad analysis of contemporary strategies and specific approaches for plausible therapeutic treatment for NDDs presented in this review could be helpful for further successful research in this area.

Cardiovascular and Neurological Outcomes in Patients Treated with Edoxaban for Atrial Fibrillation and Characteristics in Patients with Cancer

BACKGROUND

Direct oral anticoagulants (DOACs) outperform warfarin in vascular and bleeding events in atrial fibrillation (AF) patients. Yet, effects of DOACs on congestive heart failure (CHF) and Alzheimer's disease (AD) remain less explored.

METHODS

Using the Taiwan National Health Insurance Research Database, a nationwide retrospective cohort study was conducted. The study matched 5,683 non-valvular atrial fibrillation (NVAF) edoxaban patients with 11,366 warfarin patients, and 703 NVAF with cancer (NVAF-C) edoxaban patients with 1,406 warfarin patients. Vasular and non-vascular outcomes, with focuses on CHF and AD, were compared between the edoxaban and warfarin users.

RESULTS

Edoxaban significantly lowered adjusted hazrad ratio (aHR) of all-cause mortality, hospitalization for gastrointestinal bleeding, and CHF (0.37, 0.74, and 0.26, respectively, in NVAF; 0.39, 0.67, and 0.31, respectively, in NVAF-C, all p < 0.05), compared to warfarin. Edoxaban was associated with significantly lower aHRs of acute myocardial infarction, peripheral artery disease, venous thromboembolism, pulmonary embolism, and AD (0.71, 0.48, 0.55, 0.20, and 0.66, respectively; all p < 0.05) in NVAF patients versus warfarin. However, edoxaban had higher aHR of hospitalized bleeding (1.19, p = 0.002) than warfarin in NVAF patients, but not in NVAF-C patients.

CONCLUSIONS

Edoxaban demonstrated lowered CHF risks in both NVAF and NVAF-C patients, and reduced AD occurrence in NVAF patients versus warfarin. These findings advocate for edoxaban's use in AF cases.

CLINICAL PERSPECTIVE

What Is New?: The study reveals that in patients with atrial fibrillation (AF), edoxaban, a direct oral anticoagulant (DOAC), demonstrates significant advantages over warfarin. Notably, edoxaban is associated with a reduced risk of congestive heart failure (CHF) and Alzheimer's disease (AD) when compared to warfarin.Clinical Implications?: These findings have important clinical implications. Edoxaban appears to be a superior anticoagulant choice for AF patients, as it lowers the risk of CHF and AD. This highlights the potential of edoxaban to improve patient outcomes and underscores its relevance for managing AF cases.

The Role of Inhaled Estradiol and Myrtenol, Alone and in Combination, in Modulating Behavioral and Functional Outcomes Following Traumatic Experimental Brain Injury: Hemodynamic, Molecular, Histological and Behavioral Study

BACKGROUND

Traumatic brain injury (TBI) is an important and growing cause of disability worldwide, and its cognitive consequences may be particularly significant. This study assessed the neuroprotective impacts of estradiol (E2), myrtenol (Myr), and the combination of the two on the neurological outcome, hemodynamic parameters, learning and memory, brain-derived neurotrophic factor (BDNF) level, phosphoinositide 3-kinases (PI3K/AKT) signaling, and inflammatory and oxidative factors in the hippocampus after TBI.

METHODS

Eighty-four adult male Wistar rats were randomly divided into 12 groups with seven rats in each (six groups to measure intracranial pressure, cerebral perfusion pressure, brain water content, and veterinary coma scale, and six groups for behavioral and molecular studies): sham, TBI, TBI/vehicle, TBI/Myr, TBI/E2, and TBI/Myr + E2 (Myr 50 mg/kg and E2 33.3 μg/kg via inhalation for 30 min after TBI induction). Brain injury was induced by using Marmarou's method. Briefly, a 300-g weight was dropped down from a 2-m height through a free-falling tube onto the head of the anesthetized animals.

RESULTS

Veterinary coma scale, learning and memory, brain water content, intracranial pressure, and cerebral perfusion pressure were impaired following TBI, and inflammation and oxidative stress were raised in the hippocampus after TBI. The BDNF level and PI3K/AKT signaling were impaired due to TBI. Inhalation of Myr and E2 had protective effects against all negative consequences of TBI by decreasing brain edema and the hippocampal content of inflammatory and oxidant factors and also by improving BDNF and PI3K/AKT in the hippocampus. Based on these data, there were no differences between alone and combination administrations.

CONCLUSIONS

Our results propose that Myr and E2 have neuroprotective effects on cognition impairments due to TBI.

Effects of voluntary, and forced exercises on neurotrophic factors and cognitive function in animal models of Parkinson's disease

BACKGROUND

Parkinson's disease (PD) is one of the most common neurodegenerative diseases in the elderly. Cognitive dysfunction represents a common and challenging non-motor symptom for people with Parkinson's disease. The number of neurotrophic proteins in the brain is critical in neurodegenerative diseases such as Parkinson's. This research aims to compare the effects of two types of exercise, forced and voluntary, on spatial memory and learning and neurochemical factors (CDNF and BDNF).

METHODS

In this research, 60 male rats were randomly divided into six groups (n = 10): the control (CTL) group without exercise, the Parkinson's groups without and with forced (FE) and voluntary (VE) exercises, and the sham groups (with voluntary and forced exercise). The animals in the forced exercise group were placed on the treadmill for four weeks (five days a week). At the same time, voluntary exercise training groups were placed in a special cage equipped with a rotating wheel. At the end of 4 weeks, learning and spatial memory were evaluated with the Morris water maze test. BDNF and CDNF protein levels in the hippocampus were measured by the ELISA method.

RESULTS

The results showed that although the PD group without exercise was at a significantly lower level than other groups in terms of cognitive function and neurochemical factors, both types of exercise, could improve these problems.

CONCLUSION

According to our results, 4 weeks of voluntary and forced exercises were all found to reverse the cognitive impairments of PD rats.

Adiponectin receptor 1 could explain the sex differences in molecular basis of cognitive improvements induced by exercise training in type 2 diabetic rats

Adipokines dysregulation, the main reason for cognitive impairments (CI) induced by diabetes, shows a sex-dependent pattern inherently and in response to exercise. This study aimed to compare the attenuating effect of 8-week high intensity-interval training (HIIT) on type 2 diabetes (T2D)-induced CI between male and female rats with a special focus on adiponectin and leptin. 28 male & 28 female Wistar rats with an average age of 8 weeks were randomly assigned into four groups: control (Con), exercise (EX), Diabetes (T2D), and Type 2 diabetes + exercise (T2D + Ex). Rats in EX and T2D + EX groups performed HIIT for eight weeks (80-100% Vmax, 4-10 intervals). T2D was induced by 2 months of a high-fat diet and a single dose of STZ (35 mg/kg) administration. Leptin and adiponectin levels in serum were measured along with hippocampal expression of leptin and adiponectin receptors, AMP-activated protein kinase (AMPK), dephosphorylated glycogen synthase kinase-3 beta (Dep-GSK3β), Tau, and beta-amyloid (Aβ). Homeostasis model assessments (HOMAs) and quantitative insulin-sensitivity check index (QUICKI) indices were calculated. Our results showed that following T2D, serum levels of APN, and hippocampal levels of adiponectin receptor 1 (APNR1) were higher and HOMA-IR was lower in female than male rats (P < 0.05). However, after 8 weeks of HIIT, hippocampal levels of APNR1 and AMPK as well as QUICKI were lower and hippocampal levels of GSK, Tau, and Aβ were higher in females compared to male rats (P < 0.05). While the risk of CI following T2D was more in male than female rats HIIT showed a more ameliorating effect in male animals with APN1 as the main player.

The Diabetic Lung Can Be Ameliorated by Citrullus colocynthis by Reducing Inflammation and Oxidative Stress in Rats with Type 1 Diabetes

Background

Diabetes impacts various organs in the body and some reports showed that the lung is also affected by diabetes, and an imbalance of inflammation and oxidative stress may participate to diabetic lung impairments. The present study is conducted to assess the impacts of Citrullus colocynthis (CC) on some aspects of these impairments.

Methods

Frothy two male Wistar rats (3-4 months old and weighing 200-250 g) were used in the present research. Animals were divided into 3 groups of control, Diabetes, and Diabetes + Drug. CC was administered to diabetic rats orally. The lung tissue and BALF oxidative stress and inflammatory indices including the MDA, TAC, SOD, Gpx, TNFα, IL-6, IL-17, and IL-10 were evaluated by the ELISA method.

Results

Our observations disclosed the ameliorative impacts of CC administration against oxidative stress and inflammation imbalance. Also, it was found that CC improved body weight and fasting blood sugar in rats with diabetes.

Conclusion

We can conclude that the administration of CC can be effective in improving diabetic lungs in rats.

High-Intensity Interval Training Ameliorates Molecular Changes in the Hippocampus of Male Rats with the Diabetic Brain: the Role of Adiponectin

Alzheimer's disease (AD) is closely related to type 2 diabetes (T2D). This study investigated the impact of high-intensity interval training (HIIT) on diabetes-induced disturbances in AD-related factors (including AMP-activated protein kinase (AMPK), glycogen synthase kinase-3β (GSK3β), and tau protein) in the hippocampus, with the main focus on adiponectin signaling.In total, 28 male Wistar rats at the age of 8 weeks were randomly assigned to four groups (n = 7 in each group): control (Con), type 2 diabetes (T2D), HIIT (Ex), and type 2 diabetes + HIIT (T2D + Ex). T2D was induced by a high-fat diet plus a single dose of streptozotocin (STZ). Rats in Ex and T2D + Ex groups performed 8 weeks of HIIT (running at 8-95% of V_max, 4-10 intervals). Insulin and adiponectin levels in serum and hippocampus were measured along with hippocampal expression of insulin and adiponectin receptors, phosphorylated AMPK, dephosphorylated GSK3β, and phosphorylated tau. Homeostasis model assessment for insulin resistance (HOMA-IR), homeostasis model assessment for insulin resistance beta (HOMA-β), and quantitative insulin sensitivity check index (QUICKI) were calculated to assess insulin resistance and sensitivity. T2D decreased insulin and adiponectin levels in serum and hippocampus, as well as the hippocampal levels of insulin and adiponectin receptors and AMPK, but increased GSK3β and tau in the hippocampus. HIIT reversed diabetes-induced impairments and consequently decreased tau accumulation in the hippocampus of diabetic rats. HOMA-IR, HOMA-β, and QUICKI were improved in Ex and T2D + Ex groups. Overall, our results confirmed that T2D has undesirable effects on the levels of some Alzheimer's-related factors in the hippocampus, and HIIT could ameliorate these impairments in the hippocampus.

Effects of Dabigatran on Dementia Pathogenesis and Neuropsychological Function: A Review

BACKGROUND

Patients with atrial fibrillation (AF) carry higher risks of cognitive consequences and psychological burden. An optimal anticoagulant therapy would be expected to better preserve neuropsychological function in addition to effective prevention of stroke and systemic thromboembolism.

OBJECTIVE

The aim of this review is to explore the effects of the non-vitamin K antagonist oral anticoagulant (NOAC) dabigatran, a direct thrombin inhibitor, on cognitive and psychological function as well as dementia pathogenesis.

METHODS

We performed a comprehensive search of PubMed/Medline for all types of relevant articles using a combination of dabigatran and associated keywords updated to August 31, 2021. All titles and abstracts were screened for eligibility, and potentially relevant papers were collected for inclusion.

RESULTS

The pooled results demonstrated neutral to positive impacts of dabigatran on cognitive and psychological outcomes, including laboratory results in animal models of Alzheimer's disease, and reduced incidences of anxiety/depression and dementia for AF patients. Dabigatran also exhibited better therapeutic profiles than warfarin in preclinical and observational research.

CONCLUSION

Given limited strength of evidence from heterogeneous studies, our review proposed modest beneficial effects of dabigatran on neuropsychological function. Further clinical trials are warranted to affirm the pleiotropic protective effects of NOACs on dementia treatment.