Musashi-2 causes cardiac hypertrophy and heart failure by inducing mitochondrial dysfunction through destabilizing Cluh and Smyd1 mRNA

Regulation of RNA stability and translation by RNA-binding proteins (RBPs) is a crucial process altering gene expression. Musashi family of RBPs comprising Msi1 and Msi2 is known to control RNA stability and translation. However, despite the presence of MSI2 in the heart, its function remains largely unknown. Here, we aim to explore the cardiac functions of MSI2. We confirmed the presence of MSI2 in the adult mouse, rat heart, and neonatal rat cardiomyocytes. Furthermore, Msi2 was significantly enriched in the heart cardiomyocyte fraction. Next, using RNA-seq data and isoform-specific PCR primers, we identified Msi2 isoforms 1, 4, and 5, and two novel putative isoforms labeled as Msi2 6 and 7 to be expressed in the heart. Overexpression of Msi2 isoforms led to cardiac hypertrophy in cultured cardiomyocytes. Additionally, Msi2 exhibited a significant increase in a pressure-overload model of cardiac hypertrophy. We selected isoforms 4 and 7 to validate the hypertrophic effects due to their unique alternative splicing patterns. AAV9-mediated overexpression of Msi2 isoforms 4 and 7 in murine hearts led to cardiac hypertrophy, dilation, heart failure, and eventually early death, confirming a pathological function for Msi2. Using global proteomics, gene ontology, transmission electron microscopy, seahorse, and transmembrane potential measurement assays, increased MSI2 was found to cause mitochondrial dysfunction in the heart. Mechanistically, we identified Cluh and Smyd1 as direct downstream targets of Msi2. Overexpression of Cluh and Smyd1 inhibited Msi2-induced cardiac malfunction and mitochondrial dysfunction. Collectively, we show that Msi2 induces hypertrophy, mitochondrial dysfunction, and heart failure.

ACE2/ANG-(1-7)/Mas receptor axis activation prevents inflammation and improves cognitive functions in streptozotocin induced rat model of Alzheimer's disease-like phenotypes

Activation of the renin-angiotensin system (RAS), by Angiotensin converting enzyme/Angiotensin II/Angiotensin receptor-1 (ACE/Ang II/AT1 R) axis elicits amyloid deposition and cognitive impairment. Furthermore, ACE2 induced release of Ang-(1-7) binds with the Mas receptor and autoinhibits ACE/Ang II/AT1 axis activation. Inhibition of ACE by perindopril has been reported to improve memory in preclinical settings. However, the functional significance and mechanism by which ACE2/Mas receptor regulate cognitive functions and amyloid pathology is not known. The present study is aimed to determine the role of ACE2/Ang-(1-7)/Mas receptor axis in STZ induced rat model of Alzheimer's disease (AD). We have used pharmacological, biochemical and behavioural approaches to identify the role of ACE2/Ang-(1-7)/Mas receptor axis activation on AD-like pathology in both in vitro and invivo models. STZ treatment enhances ROS formation, inflammation markers and NFκB/p65 levels which are associated with reduced ACE2/Mas receptor levels, acetylcholine activity and mitochondrial membrane potential in N2A cells. DIZE mediated ACE2/Ang-(1-7)/Mas receptor axis activation resulted in reduced ROS generation, astrogliosis, NFκB level and inflammatory molecules and improved mitochondrial functions along with Ca²⁺ influx in STZ treated N2A cells. Interestingly, DIZE induced activation of ACE2/Mas receptor significantly restored acetylcholine levels and reduced amyloid-beta and phospho-tau deposition in cortex and hippocampus that resulted in improved cognitive function in STZ induced rat model of AD-like phenotypes. Our data indicate that ACE2/Mas receptor activation is sufficient to prevented cognitive impairment and progression of amyloid pathology in STZ induced rat model of AD-like phenotypes. These findings suggest the potential role of ACE2/Ang-(1-7)/Mas axis in AD pathophysiology by regulating inflammation cognitive functions.

Activation of Angiotensin-converting Enzyme 2 Protects Against Lipopolysaccharide-induced Glial Activation by Modulating Angiotensin-converting Enzyme 2/Angiotensin (1-7)/Mas Receptor Axis

Neuroinflammation is associated with activation of glial cells and pro-inflammatory arm of the central Renin Angiotensin System (RAS) namely, Angiotensin-Converting Enzyme/Angiotensin II/Angiotensin Type 1 Receptor (ACE/Ang II/AT1R) axis. Apart from this, another axis of RAS also exists, Angiotensin-Converting Enzyme 2/Angiotensin (1-7)/Mas Receptor (ACE2/Ang (1-7)/MasR), which counters ACE/Ang II/AT1R axis by showing anti-inflammatory properties. However, the role of ACE2/Ang (1-7)/MasR axis has not been explored in glial activation and neuroinflammation. Hence, the present study tries to unveil the role of ACE2/Ang (1-7)/MasR axis in lipopolysaccharide (LPS)-induced neuroinflammation using diminazene aceturate (DIZE), an ACE2 activator, in astroglial (C6) and microglial (BV2) cells as well as male SD rats. We found that ACE2 activation efficiently prevented LPS-induced changes by decreasing glial activation, inflammatory signaling, cell migration, ROS generation via upregulation of ACE2/Ang (1-7)/MasR signaling. In addition, activation of ACE2/Ang (1-7)/MasR axis by DIZE significantly suppressed the pro-inflammatory ACE/Ang II/AT1R axis by reducing Ang II level in neuroinflammatory conditions induced by LPS in both in vitro and in vivo. ACE2/Ang (1-7)/MasR axis activation further decreased mitochondrial depolarization and apoptosis, hence providing neuroprotection. Furthermore, to validate that the beneficial effect of the ACE2 activator was indeed through MasR, a selective MasR antagonist (A779) was used that significantly blocked the anti-inflammatory effect of ACE2 activation by DIZE. Hence, our study demonstrated that ACE2 activation imparted neuroprotection by enhancing ACE2/Ang (1-7)/MasR signaling which in turn decreased glial activation, neuroinflammation, and apoptosis and improved mitochondrial health.

Cissus quadrangularis extract mitigates diabetic cardiomyopathy by inhibiting RAAS activation, inflammation, and oxidative stress

IntroductionDiabetic cardiomyopathy (DCM) is an age-related disease, and its progression is accompanied by hyperglycemia, cardiac dysfunction, and myocardial structural and functional abnormalities. Cissus quadrangularis, a traditional medicinal plant, contains polyphenols, flavonoids, phytosterols, carbohydrates, and ascorbic acid. It is used to treat osteoporosis, asthma, haemorrhoids, and menstrual disorders. In the current research, we have investigated the effect of ethanolic extract of C. quadrangularis (EECQ) against a high-fat diet (HFD)/streptozotocin-induced DCM by estimating cardiac biomarkers, inflammatory markers and ROS production.Material and methodsRats were fed with an HFD for 12 weeks, followed by single-shot low-dose streptozotocin (35mg/kg; i.p.). The treatment was performed by EECQ (200 mg/kg/day, orally) for six weeks. ResultsThe extract EECQ improves glucose, insulin tolerance tests, and hypercholesteremia. DCM is characterized by cardiac dysfunction, cardiac biomarkers CKMB, and LDH, which were attenuated by the EECQ treatment. The hypertrophic biomarker ANP, BNP expression and cardiomyocyte surface area were decreased by EECQ. Moreover, EECQ also alleviated the biomarkers Angiotensin II and renin level. EECQ also reduced oxidative stress, ROS production and cardiac inflammation.ConclusionThus, these findings suggested that EECQ could be used as a possible therapeutic regiment to treat DCM.

Hepatitis A in the Eastern Mediterranean Region: a comprehensive review

Introduction

With 583 million inhabitants, the Eastern Mediterranean Region (EMR) is a worldwide hub for travel, migration, and food trade. However, there is a scarcity of data on the epidemiology of the hepatitis A virus (HAV).

Methods

The MEDLINE and grey literature were systematically searched for HAV epidemiological data relevant to the EMR region published between 1980 and 2020 in English, French, or Arabic.

Results

Overall, 123 publications were extracted. The proportion of HAV cases among acute viral hepatitis cases was high. HAV seroprevalence rate ranged from 5.7% to 100.0% and it was decreasing over time while the average age at infection increased.

Conclusion

In the EMR, HAV remains a significant cause of acute viral hepatitis. The observed endemicity shift will likely increase disease burden as the population ages. Vaccinating children and adopting sanitary measures are still essential to disease prevention; vaccinating at-risk groups might reduce disease burden even further.

What is the context?

Hepatitis A is a viral liver disease caused by the hepatitis A virus.

It is generally transmitted by ingestion of contaminated food or water or through contact with an infected person.

Disease severity increases with age. Children under 6 years of age are usually asymptomatic, while adults are the most affected.

Limited information exists on the number of cases and transmission of hepatitis A in the Eastern Mediterranean region, which includes 21 countries and Palestine, as defined by the World Health Organization.

What is new?

We performed a literature review to summarize data on hepatitis A disease in the Eastern Mediterranean region over the last 40 years (1980-2020). As information for many countries is scarce or outdated, most of the data is from Egypt, Iran and Saudi Arabia.

We found that:

Hepatitis A virus is the most common cause of acute viral hepatitis.

Hepatitis A exposure varied according to the country’s income level.

Low- and middle-income countries showed a universal immunity to hepatitis A virus, although this is not the case anymore.

What is the impact?

Hepatitis A infections have decreased worldwide. Lower exposure to the virus has led to an increase in the susceptible population (including adolescent and adults).

Hepatitis A vaccination for children and high-risk groups such travelers should be considered in the Eastern Mediterranean region.

Angiotensin-Converting Enzyme 2 Activation Mitigates Behavioral Deficits and Neuroinflammatory Burden in 6-OHDA Induced Experimental Models of Parkinson's Disease

Hypertension is reported to cause major brain disorders including Parkinson's disease (PD), apart from cardiovascular and chronic kidney disorders. Considering this, for the first time, we explored the effect of modulation of the ACE2/Ang (1-7)/MasR axis using diminazene aceturate (DIZE), an ACE2 activator, in 6-hydroxydopamine (6-OHDA) induced PD model. We found that DIZE treatment improved neuromuscular coordination and locomotor deficits in the 6-OHDA induced PD rat model. Further, the DIZE-mediated activation of ACE2 led to increased tyrosine hydroxylase (TH) and dopamine transporters (DAT) expression in the rat brain, indicating the protection of dopaminergic (DAergic) neurons from 6-OHDA induced neurotoxicity. Moreover, 6-OHDA induced activation of glial cells (astrocytes and microglia) and release of neuroinflammatory mediators were attenuated by DIZE treatment in both in vitro as well as in vivo models of PD. DIZE exerted its effect by activating ACE2 that produced Ang (1-7), a neuroprotective peptide. Ang (1-7) conferred its neuroprotective effect upon binding with the G-protein-coupled MAS receptor that led to the upregulation of cell survival proteins while downregulating apoptotic proteins. Importantly, these findings were further validated by using A-779, a MasR antagonist. The result showed that treatment with A-779 reversed the antioxidative and anti-inflammatory effects of DIZE by decreasing glial activation and neuroinflammatory markers. Although the role of ACE2 in PD pathology needs to be additionally confirmed using transgenic models in either ACE2 overexpressing or knockout mice, still, our study demonstrates that enhancing ACE2 activity could be a novel approach for ameliorating PD pathology.

Comparison of Nd: YAG (Neodymium-Doped Yttrium Aluminum Garnet) Laser Posterior Capsulotomy Techniques in The Treatment of Posterior Capsular Opacification

Objective: To compare the safety and efficacy of different techniques of neodymium: yttrium-aluminum-garnet (Nd: YAG) laser posterior capsulotomy. Study Design: Quasi-experimental study. Place and Duration of Study: Combined Military Hospital Nowshera, from Aug 2015 to Mar 2017. Methodology: A total of 120 patients fulfilling the inclusion criteria were allocated to three groups. Group-A (Circular-group, CG) patients were subjected to circular pattern capsulotomy, group-B (Hinged-group, HG) patients underwent hinged pattern capsulotomy and group-C (Modified-group, MG) had a circular pattern of Nd: YAG posterior capsulotomy along with vitreous strand cutting (modified round pattern). Primary outcome measures were the best-corrected visual acuity (BCVA), intraocular pressure (IOP) and annoying floaters at three-months follow up visits. Results: The mean age of patients was 52.27 ± 5.65 years and there were 64 (53.3%) males and 56 (46.7%) females. The bestcorrected visual acuity improved significantly (p<0.001) in the modified round pattern group compared to the other two groups at two weeks post-capsulotomy. Intraocular pressure remained unchanged among the three groups. Significantly fewer patients in the modified treatment-group experienced annoying floaters as compared to hinged and circular treatment groups [3 (7.5%) vs 9 (22.5%) vs 12 (30.0%) respectively, p=0.038]. Conclusion: Modified round pattern Nd: YAG laser posterior capsulotomy is a safe and effective method for treating posterior capsular opacification.

Involvement of mitogen-activated protein kinase (MAPK)-activated protein kinase 2 (MK2) in endothelial dysfunction associated with pulmonary hypertension

AIMS

Increased proliferation, inflammation, and endothelial microparticle (EMP) generation in the pulmonary vasculature lead to endothelial dysfunction in pulmonary hypertension (PH). Interestingly, MK2, a downstream of p38MAPK, is a central regulator of inflammation, proliferation, and EMP generation in cardiovascular diseases. However, the role of MK2 in pulmonary endothelial dysfunction remains unexplored.

MAIN METHODS

The Human Pulmonary Artery Endothelial cells (HPAECs) were exposed to hypoxia (1% O₂) for 72 h, and MK2 inhibition was achieved by siRNA treatment. Western blotting, qualitative RT-PCR, immunocytochemistry, flow cytometry and enzyme-linked immunoassays were conducted to study pathological alterations and molecular mechanisms. Neoangiogenesis was studied using cell migration and tubule formation assays. For in vivo study, Male Sprague Dawley rats and MK2 knock-out mice with littermate control were treated with monocrotaline (MCT) 60 mg/kg and 600 mg/kg, respectively (s.c. once in rat and weekly in mice) to induce PH. MMI-0100 (40 μg/kg, i.p. daily for 35 days), was administered in rats to inhibit MK2.

KEY FINDINGS

MK2 inhibition significantly decreased inflammation, cell proliferation, apoptosis resistance, and improved mitochondrial functions in hypoxic HPAECs. Hypoxia promoted cell migration, VEGF expression, and angiogenesis in HPAECs, which were also reversed by MK2 siRNA. MK2 inhibition decreased EMP generation and increased the expression of p-eNOS in hypoxic HPAECs, a marker of endothelial function. Furthermore, MK2 deficiency and inhibition both reduced the EMP generation in mice and rats, respectively.

SIGNIFICANCE

These findings proved that MK2 is involved in endothelial dysfunction, and its inhibition may be beneficial for endothelial function in PH.

The Protective Effects of AT2R Agonist, CGP42112A, Against Angiotensin II-Induced Oxidative Stress and Inflammatory Response in Astrocytes: Role of AT2R/PP2A/NFκB/ROS Signaling

Angiotensin II receptor type 2 (AT2R) agonists have been known to promote neuroprotection by limiting ischemic insult, neuronal proliferation, and differentiation. Further, AT2R agonists have also been associated with the suppression of neuroinflammation and neurodegeneration. Of note, brain astrocytes play a critical role in these neuroinflammatory and neurodegenerative processes. However, the role of AT2R in astrocytic activation remains elusive. Therefore, this study evaluated the role and molecular mechanism of AT2R agonist CGP42112A (CGP) against Angiotensin II (Ang II)-induced astrocytic activation in primary astrocytes, and in a rat model of hypertension. Here, we demonstrated that AT2R activation by CGP abrogated Ang II-induced astrocytic activation, by mitigating the ROS production, mitochondrial dysfunction, IκB-α degradation, NFκB nuclear translocation, and release of TNF-α in astrocytes. However, AT2R-mediated anti-inflammatory effects were reversed by AT2R antagonist, PD123319 (PD), in both in vitro and in vivo conditions. Mechanistically, AT2R via protein phosphatase-2A (PP2A) abrogated the Ang II-induced NFκB activation, ROS generation, and subsequent astrocytic activation. Importantly, PP2A antagonist, okadaic acid, reversed the anti-inflammatory effects of AT2R in Ang II-stimulated primary astrocytes and in the cortex of hypertensive rats. Thus, the present study suggests that AT2R by activating PP2A inhibits oxidative stress and NFκB activation, thereby preventing the astrocytic pro-inflammatory activation. Therefore, AT2R might be advantageous therapeutic target for neuroinflammatory/neurodegenerative diseases perpetuated by astrocytic activation.

Safety and Efficacy of Suprachoroidal Injection of Triamcinolone in Treating Macular Edema Secondary to Noninfectious Uveitis

Introduction 

One of the leading causes of blindness throughout the world is uveitis, which predominantly results in the feared complication of macular edema. We report the safety and efficacy of suprachoroidal injection of triamcinolone acetonide in the treatment of macular edema secondary to noninfectious uveitis. 

Methodology 

This prospective, nonrandomized interventional study was conducted at Layton Rahmatullah Benevolent Trust (LRBT) Eye Hospital, Lahore, from August 2019 till July 2020. All individuals older than 18 years, nonpregnant females with a central macular thickness of >320 µm were included. Those patients with uncontrolled diabetes, immunodeficiency, or any other disease mandating systemic corticosteroid use were excluded. All patients had a detailed ocular exam one week before the treatment, and 0.1 ml of triamcinolone acetonide 40 mg/ml was injected using a 30-G hollow needle into the suprachoroidal space. After the injection, an eye patch was applied and the patient was observed for three hours. All data were documented in a preformed proforma. 

Results

A total of 30 patients were included in the study with a mean age of 38.1 ± 9.48 years. Statistically significant differences were found between central macular thickness at presentation and at one and three months of the procedure, i.e., 569.60 ± 170.396, 266.77 ± 73.127, and 208.27 ± 37.292 µm, respectively. A similar difference was observed when comparing visual acuity at baseline to visual acuity at one and three months of the procedure (p < 0.001). 

Conclusion 

The current study indicates that a single dose of suprachoroidal injection of triamcinolone acetonide for the treatment of macular edema secondary to uveitis is safe and efficacious. No rise in intraocular pressure (IOP) was observed during the study period. Significant improvements in central macular thickness and visual acuity as well as tolerability and safety of the treatment were seen in our study. Further larger-scale studies are needed to ascertain the long-term benefits of the suprachoroidal triamcinolone acetonide.

Clinical Characteristics of Children With COVID-19 in the United Arab Emirates: Cross-sectional Multicenter Study

BACKGROUND

COVID-19 has infected over 123 million people globally. The first confirmed case in the United Arab Emirates (UAE) was reported on January 29, 2020. According to studies conducted in the early epicenters of the pandemic, COVID-19 has fared mildly in the pediatric population. To date, there is a lack of published data about COVID-19 infection among children in the Arabian region.

OBJECTIVE

This study aims to investigate the clinical characteristics, laboratory findings, treatment, and outcomes of children with COVID-19.

METHODS

This cross-sectional, multicenter study included children with confirmed COVID-19 infection admitted to 3 large hospitals in Dubai, UAE, between March 1 and June 15, 2020. Serial COVID-19 polymerase chain reaction (PCR) testing data were collected, and patients' demographics, premorbid clinical characteristics, and inpatient hospital courses were examined.

RESULTS

In all, 111 children were included in our study and represented 22 nationalities. Of these, 59 (53.2%) were boys. The mean age of the participants was 7 (SD 5.3) years. About 15.3% of children were younger than 1 year. Only 4 (3.6%) of them had pre-existing asthma, all of whom had uneventful courses. At presentation, of the 111 children, 43 (38.7%) were asymptomatic, 68 (61.2%) had mild or moderate symptoms, and none (0%) had severe illness requiring intensive care. Fever (23/111, 20.7%), cough (22/111, 19.8%), and rhinorrhea (17/111, 15.3%) were the most common presenting symptoms, and most reported symptoms resolved by day 5 of hospitalization. Most patients had no abnormality on chest x-ray. The most common laboratory abnormalities on admission included variations in neutrophil count (22/111, 24.7%), aspartate transaminase (18/111, 22.5%), alkaline phosphatase (29/111, 36.7%), and lactate dehydrogenase (31/111, 42.5%). Children were infrequently prescribed targeted medications, with only 4 (3.6%) receiving antibiotics. None of the 52 patients tested for viral coinfections were positive. COVID-19 PCR testing turned negative at a median of 10 days (IQR: 6-14) after the first positive test. Overall, there was no significant difference of time to negative PCR results between symptomatic and asymptomatic children.

CONCLUSIONS

This study of COVID-19 presentations and characteristics presents a first look into the burden of COVID-19 infection in the pediatric population in the UAE. We conclude that a large percentage of children experienced no symptoms and that severe COVID-19 disease is uncommon in the UAE. Various laboratory abnormalities were observed despite clinical stability. Ongoing surveillance, contact tracing, and public health measures will be important to contain future outbreaks.

Ethanolic extract of Cissus quadrangularis improves vasoreactivity by modulation of eNOS expression and oxidative stress in spontaneously hypertensive rats

BACKGROUND

Endothelial dysfunction is related to the reduced bioavailability of nitric oxide (NO) and plays a significant role in developing hypertension. The intake of a diet rich in antioxidants decreases the threat of hypertension. Cissus quadrangularis possesses antioxidant, anti-inflammatory, and hypocholesterolemic activities. However, to date, no studies have been performed to explore this plant's antihypertensive and vasorelaxant activity. Herein, we investigated the chronic effect of C. quadrangularis on blood pressure as well as vascular function in hypertensive rats.

METHODS

Male spontaneously hypertensive rats (SHR) were randomly divided into two groups. Normotensive Wistar rats were taken as the control group. The treatment was done using ethanolic extract of C. quadrangularis (EECQ) at a dose of 200 mg/kg.

RESULTS

The administration of EECQ for six weeks reduced the systolic blood pressure, mean arterial blood pressure, and heart rate. It also alleviated the cardiac and renal hypertrophy indices. Supplementation of EECQ improved the endothelium-dependent aortic vasodilation induced by acetylcholine. It restored the NO level and endothelial NO synthase expression in the aorta. Subsequently, the extract alleviates the oxidative stress and inflammatory markers in SHR rats.

CONCLUSION

Thus, in the present study, the chronic treatment of EECQ to genetically hypertensive rats improved endothelium-dependent relaxation in addition to its antihypertensive effect by eNOS activation and inhibition of ROS production, inflammation.

Coupling of electrocoagulation and powder activated carbon for the treatment of sustainable wastewater

The present research work is based on an electrochemical technique in combination with powdered activated carbon (PAC) for the removal of micropollutants by adsorption as an advanced stage purification step from effluents of pilot plant wastewater treatment plants (WWTP). The effluents of sedimentation tank comprised of wastewater plus PAC (WWPAC). The pilot plant mainly consists of two parts: the first one consists of electrocoagulation (EC) reactor, and the second consists of electrophoretic deposition (EPD) discs and electroflotation (EF) setup. The electrocoagulation (EC) reactor consisted of the electrode material (Al and Fe). Both types of electrodes have been tested with the outflow of sedimentation tank. The outflow from the sedimentation tank has been entered into the EC reactor for the determination of EC reactor efficacy for the successful accomplishment of EC process at the designed pilot plant for WW treatment. The effect of different operational parameters, PAC dosage (20 mg), electrode nature (Fe and Al) and current density (0.34-2.02 A/m²), has been studied to find out the optimum conditions. Sludge volume index (SVI) of the sludge, thermogravimetric (TG), differential thermal analyses (DTA) and particle size distribution (PSD) of the flocs generated after the EC process has also been studied. The turbidity, pH and conductivity of effluents before and after EC treatment have also been carried out. The research work performed detailed analysis of the wastewater effluents at pilot plant scale and gave promising results for future work in advance wastewater treatment direction.

Regulatory safety pharmacology and toxicity assessments of a standardized stem extract of Cassia occidentalis Linn. in rodents

Cassia occidentalis Linn (CO) is an annual/perennial plant having traditional uses in the treatments of ringworm, gastrointestinal ailments and piles, bone fracture, and wound healing. Previously, we confirmed the medicinal use of the stem extract (ethanolic) of CO (henceforth CSE) in fracture healing at 250 mg/kg dose in rats and described an osteogenic mode of action of four phytochemicals present in CSE. Here we studied CSE's preclinical safety and toxicity. CSE prepared as per regulations of Current Good Manufacturing Practice for human pharmaceuticals/phytopharmaceuticals and all studies were performed in rodents in a GLP-accredited facility. In acute dose toxicity as per New Drug and Clinical Trial Rules, 2019 (prior name schedule Y), in rats and mice and ten-day dose range-finding study in rats, CSE showed no mortality and no gross abnormality at 2500 mg/kg dose. Safety Pharmacology showed no adverse effect on central nervous system, cardiovascular system, and respiratory system at 2500 mg/kg dose. CSE was not mutagenic in the Ames test and did not cause clastogenicity assessed by in vivo bone marrow genotoxicity assay. By a sub chronic (90 days) repeated dose (as per OECD, 408 guideline) study in rats, the no-observed-adverse-effect-level was found to be 2500 mg/kg assessed by clinico-biochemistry and all organs histopathology. We conclude that CSE is safe up to 10X the dose required for its osteogenic effect.

Antihypertensive Effect of a Novel Angiotensin II Receptor Blocker Fluorophenyl Benzimidazole: Contribution of cGMP, Voltage-dependent Calcium Channels, and BKCa Channels to Vasorelaxant Mechanisms

Background: The current study presents the novel angiotensin II receptor blocker fluorophenyl benzimidazole (FPD) as an antihypertensive agent in the SHR model of hypertension. We investigated the role of cGMP, voltage-dependent L-type calcium channels, and BK_Ca channels in the vasorelaxant mechanisms of FPD in the rat superior mesenteric artery.

Methods: The antihypertensive effect of FPD was examined using an invasive technique measuring blood pressure in SHR animals. Using a myograph, tension measurement was completed in the superior mesenteric artery to elucidate the mechanisms of vasorelaxation involving AT1 receptors, the NO/cGMP pathway, L-type calcium channels, and BK_Ca channels. Ion flux (Ca²⁺, K⁺) studies were conducted in aortic smooth muscle cells. Putative targets proteins were determined by in silico docking studies. A safety evaluation of FPD was carried out using Swiss albino mice.

Results: FPD significantly decreased blood pressure in SHR. It relaxed superior mesenteric arteries in a concentration-dependent manner and significantly inhibited angiotensin II-induced contraction. The relaxation response was also mediated by an increase in tissue cGMP levels, inhibition of L-type calcium channels, and the opening of BK_Ca channels. FPD further enhanced efflux of K⁺ and inhibited Bay K8644-stimulated Ca²⁺ influx in aortic smooth muscle cells and docked well in an in silico study with the targets. It was well tolerated in the toxicity study.

Conclusion: The present study reports the antihypertensive activity of novel AT-1 receptor blocker FPD at 50 and 100 mg kg⁻¹ with cGMP, L-type calcium channels, and BK_Ca channels as putative targets of vasorelaxation, and was found safe in oral toxicity.

Inhibition of Mitogen-Activated Protein Kinase (MAPK)-Activated Protein Kinase 2 (MK2) is Protective in Pulmonary Hypertension

[Figure: see text].

Removal of micropollutants from municipal wastewater using different types of activated carbons

The water reservoirs are getting polluted due to increasing amounts of micropollutants such as pharmaceuticals, organic polymers and suspended solids. Powdered activated carbon (PAC) has been proved to be a promising solution for the purification of water without having harmful impacts on the environment. Parameters such as PAC dosing, wastewater hardness, the effect of coagulant and flocculant were evaluated in a batch scale study. These parameters were further applied on a pilot plant scale for the performance evaluation of PAC based removal of micropollutants concerning the contact time and PAC dosing with main focus on recirculation of PAC sludge. The obtained optimum dose was 10-20 mg/L providing 84.40-91.30% removal efficiency of suspended solid micropollutants (MPs) and this efficiency increased to 88.90-93.00% along with coagulant which further raised by the addition of polymer and recirculation process at batch scale. On pilot plant scale, the concentration in contact reactor and PAC removal effectiveness of dissolved air flotation, lamella separator and sedimentation tank were compared. Constant optimisation resulted in a concentration ranging from 2.70 to 3.40 g/L at dosing of PAC 10 mg/L, coagulant 2.00 mg/L and polymer 0.50 mg/L. PAC doses of 10-20 mg/L with 15-30 min contact time proved best for above 70-80% elimination. The recirculation system has also proved an efficient technique because the PAC's adsorption capacity was practically completely used. Small PAC dosages yielded high micropollutants elimination.

Naringin ameliorates type 2 diabetes mellitus-induced steatohepatitis by inhibiting RAGE/NF-κB mediated mitochondrial apoptosis

AIMS

Recent findings have instituted the role of hyperglycemia-related AGE/RAGE and NF-κB in instigating reactive oxygen species (ROS) mediated mitochondrial dysfunction and apoptosis of hepatocyte, which leads to steatohepatitis. Naringin, a flavanone glycoside found to possess myriads of pharmacological benefits along with its antioxidant and anti-inflammatory properties. Consequently, we aimed to decipher the effect of naringin on RAGE/NF-κB mediated mitochondrial apoptosis in type 2 diabetes mellitus (T2DM)-induced steatohepatitis.

MAIN METHODS

Hepatic HepG2 cells were cultured in palmitic acid medium with and without naringin. Lipid content was examined by Oil Red O and Nile Red staining. Cellular apoptosis was determined by Annexin V-FITC/PI staining. An experimental T2DM-induced steatohepatitis was developed in Sprague Dawley rats by high-fat diet (HFD) for 12 weeks. The naringin was administrated orally at a dose of 100 mg/kg, daily for eight weeks. Glucose and insulin tolerance test was performed. Liver sections were stained by hematoxylin-eosin and picrosirius red. The mRNA and protein expression of RAGE and NF-κB were determined by qPCR, Immunofluorescence, and Immunoblotting. Mitochondrial membrane potential (MMP), cellular and mitochondrial ROS were measured by FACS.

KEY FINDINGS

Palmitic acid encountered HepG2 cells and HFD fed rats exhibited hyperlipidemia, insulin resistance, abnormal aminotransferases, steatosis, and fibrosis. Besides, the level of AGEs, RAGE, NF-κB, and oxidative stress were exacerbated. Moreover, MMP, cellular and mitochondrial ROS were altered in diabetic rats. Nevertheless, the naringin treatment ameliorated the steatohepatitis by improving the levels of aforementioned parameters.

SIGNIFICANCE

Collectively, these findings suggested anti-steatohepatitis potential of naringin in diabetics.

Involvement of angiotensin II and beta-adrenergic receptors in the regulation of autophagy in human endothelial EA.hy926 cell line

Purpose: To investigate the role of angiotensin II (Ang II) and β adrenergic receptors (βARs) in autophagy regulation in human endothelial EA.hy926 cell line.Methods: The effect of pharmacological modulation of Ang II receptors and βARs on the expression of LC3B-II and p62 proteins (autophagosome formation marker and autophagic flux marker, respectively) in the human endothelial EA.hy926 cell line were investigated by immunoblotting technique.Results: Ang II-induced autophagy was characterized by increased LC3B-II and reduced p62 expressions. Candesartan, an AT1R agonist,  significantly suppressed the effects of Ang II, while a selective AT2R antagonist, PD123319, inhibited the effect of candesartan. An AT2R agonist, CGP-42112A, also suppressed the Ang II-induced autophagy. Treatment with isoproterenol enhanced the expression of LC3B-II and reduced that of p62; these effects were suppressed upon cotreatment with propranolol (non-selective βAR blocker propranolol). A selective β1AR agonist, dobutamine, reduced the expression of LC3B-II, and increased that of p62; the same was suppressed upon treatment with a selective β1AR antagonist, metoprolol. A selective β2AR agonist, salbutamol, resulted in increased expression of LC3B-II and reduced expression of p62. These effects were encountered upon treatment with selective β2AR antagonist, ICI-118,551.Conclusion: Based on the foregoing, it is evident that AT1Rs mediates Ang II-induced endothelial cell autophagy, while AT2Rs antagonizes the mechanism. βAR activation mediates isoproterenol-induced endothelial cell autophagy, which results from the balance of β1ARs-mediated suppression and β2ARsmediated upregulation of autophagy in the endothelial cells. Keywords: Autophagy, Angiotensin II type 1 receptors, Angiotensin II type 2 receptors β adrenergic type 1 receptors, β adrenergic type 2 receptors endothelial cells

Autophagy inhibition by chloroquine prevents increase in blood pressure and preserves endothelial functions

Purpose: To determine the effects of lysosomal inhibition of autophagy by chloroquine (CHQ) onhypertension-associated changes in the endothelial functions. Method: Angiotensin II (Ang II)-treated human endothelial cell line EA.hy926 and renovascularhypertensive rats were subjected to CHQ treatment (in vitro: 0.5, 1, and 2.5 μM; in vivo: 50 mg/kg/dayfor three weeks). Changes in the protein expressions of LC3b II (autophagosome formation marker) andp62 (autophagy flux marker) were assessed using immunoblotting. Cell migration assay, tubuleformation assay (in vitro), and organ bath studies (in vivo) were performed to evaluate the endothelialfunctions. Hemodynamic parameters were measured as well. Results: A higher expression of LC3b II and a reduced expression of p62 observed in the Ang II-treatedendothelial cells, as well as in the aorta of the hypertensive rats, indicated enhanced autophagy.Treatment with CHQ resulted in reduced autophagy flux (in vitro as well as in vivo) and suppressed AngII-induced endothelial cell migration and angiogenesis (in vitro). The treatment with CHQ was alsoobserved to prevent increase in blood pressure in hypertensive rats and preserved acetylcholineinducedrelaxation in phenylephrine-contracted aorta from the hypertensive rats. In addition, chloroquineattenuated Ang II-induced contractions in the aorta of normotensive as well as hypertensive rats. Conclusion: These observations indicated that CHQ lowers the blood pressure and preserves thevascular endothelial function during hypertension. Keywords: Angiotensin II, Autophagy, Chloroquine, Endothelial function, Hypertension, Vasculardysfunction

Systematic review of the rotavirus infection burden in the WHO-EMRO region

Rotavirus gastroenteritis imposes a heavy burden on low- and middle-income countries. The World Health Organization defines the Eastern Mediterranean region (WHO-EMRO) as a diverse area in terms of socioeconomic status and health indicators. Rotavirus vaccination has been introduced, at least partially, in 19 out of the 22 EM countries; however, vaccine coverage remains low, and data on rotavirus disease burden is scarce.Available data on rotavirus prevalence, seasonality, vaccination status, and genotype evolution was systematically compiled following a literature review that identified 165 relevant WHO-EMRO epidemiology studies published between 1990 and 2017.Although the infectious agents responsible for acute gastroenteritis vary over time, rotavirus remained the leading cause of acute gastroenteritis in children, as seen in 76.3% of reviewed publications. Younger children (<2 years old) were at higher risk and thus increased vaccination coverage and surveillance systems are required to reduce the rotavirus gastroenteritis burden in WHO-EMRO countries.

Platelet CD40L induces activation of astrocytes and microglia in hypertension

Studies have demonstrated separately that hypertension is associated with platelet activation in the periphery (resulting in accumulation and localized inflammatory response) and glial activation in the brain. We investigated the contribution of platelets in brain inflammation, particularly glial activation in vitro and in a rat model of hypertension. We found that HTN increased the expression of adhesion molecules like JAM-1, ICAM-1, and VCAM-1 on brain endothelium and resulted in the deposition of platelets in the brain. Platelet deposition in hypertensive rats was associated with augmented CD40 and CD40L and activation of astrocytes (GFAP expression) and microglia (Iba-1 expression) in the brain. Platelets isolated from hypertensive rats had significantly higher sCD40L levels and induced more prominent glial activation than platelets from normotensive rats. Activation of platelets with ADP induced sCD40L release and activation of astrocytes and microglia. Moreover, CD40L induced glial (astrocytes and microglia) activation, NFкB and MAPK inflammatory signaling, culminating in neuroinflammation and neuronal injury (increased apoptotic cells). Importantly, injection of ADP-activated platelets into normotensive rats strongly induced activation of astrocytes and microglia and increased plasma sCD40L levels compared with control platelets. On the contrary, inhibition of platelet activation by Clopidogrel or disruption of CD40 signaling prevented astrocyte and microglial activation and provided neuroprotection in both in vivo and in vitro conditions. Thus, we have identified platelet CD40L as a key inflammatory molecule for the induction of astrocyte and microglia activation, the major contributors to inflammation-mediated injury in the brain.

Cardioprotective Effect of Ulmus wallichiana Planchon in β-Adrenergic Agonist Induced Cardiac Hypertrophy

Ulmus wallichiana Planchon (Family: Ulmaceae), a traditional medicinal plant, was used in fracture healing in the folk tradition of Uttarakhand, Himalaya, India. The present study investigated the cardioprotective effect of ethanolic extract (EE) and butanolic fraction (BF) of U. wallichiana in isoprenaline (ISO) induced cardiac hypertrophy in Wistar rats. Cardiac hypertrophy was induced by ISO (5 mg/kg/day, subcutaneously) in rats. Treatment was performed by oral administration of EE and BF of U. wallichiana (500 and 50 mg/kg/day). The blood pressure (BP) and heart rate (HR) were measured by non-invasive blood pressure measurement technique. Plasma renin, Ang II, NO, and cGMP level were estimated using an ELISA kit. Angiotensin converting enzyme activity was estimated. BP and HR were significantly increased in ISO group (130.33 ± 1.67 mmHg vs. 111.78 ± 1.62 mmHg, p < 0.001 and 450.51 ± 4.90 beats/min vs. 347.82 ± 6.91 beats/min, respectively, p < 0.001). The BP and HR were significantly reduced (EE: 117.53 ± 2.27 mmHg vs. 130.33 ± 1.67 mmHg, p < 0.001, BF: 119.74 ± 3.32 mmHg vs. 130.33 ± 1.67 mmHg, p < 0.001); HR: (EE: 390.22 ± 8.24 beats/min vs. 450.51 ± 4.90 beats/min, p < 0.001, BF: 345.38 ± 6.79 beats/min vs. 450.51 ± 4.90 beats/min, p < 0.001) after the treatment of EE and BF of U. wallichiana, respectively. Plasma renin, Ang II, ACE activity was decreased and NO, cGMP level were increased. The EE and BF of U. wallichiana down regulated the expression of ANP, BNP, TNF-α, IL-6, MMP9, β1-AR, TGFβ1 and up regulated NOS3, ACE2 and Mas expression level, respectively. Thus, this study demonstrated that U. wallichiana has cardioprotective effect against ISO induced cardiac hypertrophy.

Evaluation of anti-hypertensive activity of Ulmus wallichiana extract and fraction in SHR, DOCA-salt- and L-NAME-induced hypertensive rats

ETHNOPHARMACOLOGICAL RELEVANCE

Ulmus wallichiana Planchon (Himalayan Elm), a traditional medicinal plant, used in fracture healing in folk tradition of Uttarakhand, Himalaya, India. It is also used as diuretic. U. rhynchophylla, native to China, known as Gou Teng in Chinese medicine, is used for hypertension (WHO). U. macrocarpa has antihypertensive and vasorelaxant activity. However, no detailed studies related to hypertension have been reported previously, so we have explored the antihypertensive activity of U. wallichiana.

AIM OF THE STUDY

To investigate the pharmacological effect of ethanolic extract (EE) and butanolic fraction (BF) of U. wallichiana in hypertensive rats.

MATERIALS AND METHODS

SHR, DOCA-salt- and L-NAME-induced hypertension models were used. Treatment was performed by oral administration of EE and BF of U. wallichiana (500mg/kg/day and 50mg/kg/day) for 14 days. Then blood pressure was measured by non-invasive blood pressure (NIBP) measurement technique. Invasive blood pressure (IBP) was also reported to support the NIBP data. Concentrations of plasma renin, angiotensin II (Ang II), nitrate/nitrite (NO), cGMP were estimated. Angiotensin-converting enzyme (ACE) activity and ROS activity were also estimated.

RESULTS

Blood pressure was significantly higher in SHR as compared to normotensive wistar group (170.59±0.83mmHg vs 121.54±1.24mmHg, respectively). SBP was increased in DOCA-salt induced group compared to their control (132.77±3.90mmHg vs 107.85±5.95mmHg, respectively) and L-NAME-induced group compared to their control (168.55±5.07mmHg vs 113.03±4.13mmHg, respectively). The treatment of extract and fraction of U. wallichiana significantly decreased the blood pressure in SHR+EE (151.26±1.85mmHg, p<0.001), SHR+BF (140.44±1.16mmHg, p<0.001); DOCA+EE (113.43±5.44mmHg, p<0.05), DOCA+BF (105.09±5.12mmHg, p<0.05) and L-NAME+EE (119.76±4.39mmHg, p<0.001), L-NAME+BF (117.50±7.27mmHg, p<0.001) compared to their respective diseased control groups. The plasma renin, Ang II and ACE activity were also significantly decreased and augmented the NO and cGMP levels. It also down regulated the expression of Renin, ACE, NOS3 and TGF-β1 at mRNA levels.

CONCLUSIONS

The EE and BF probably reducing the BP via Renin-angiotensin-aldosterone system and NO/cGMP signaling pathway. The decrease in blood pressure may be due to presence of quercetin analogue flavonoids (2S,3S)-(+)-3',4',5,7-tetrahydroxydihydroflavonol-6-C-β-D-glucopyranoside; 6-Glucopyranosyl-3,3',4',5,7-pentahydroxyflavone; 6-Glucopyranosyl-4',5,7-trihydroxyflavanone and (2S,3S)-(+)-4',5,7-trihydroxydihydroflavonol-6-C-β-D-glucopyranoside, may be due to its antioxidant activity. Thus EE and BF of U. wallichiana found to have the potential ability to be used as herbal medicament to treat hypertension.

Evidence of Coxiella burnetii in Punjab province, Pakistan

Coxiella burnetii causes query (Q) fever, an important zoonotic disease with worldwide significance. The role of environment in the ecology of C. burnetti, and its influence on seroconversion in animals has not been elucidated in Pakistan. We carried out a cross-sectional study in Punjab province to (1) determine the prevalence and distribution of C. burnetii in soil using an ISIIII gene-based real time-polymerase chain reaction (RT-PCR) assay, (2) analyze association between the occurrence of C. burnetii in soil and its predictors i.e. soil characteristics (macro- and micro-nutrients) and several likely risk factors including the seroconversion in small ruminants at places where its genome had or had not been detected, and (3) predict homology and genetic diversity of the identified strains using sequences originated from different hosts worldwide. A total of 2425 soil samples from nine districts of Punjab province were processed. C. burnetii DNA was detected in 47 samples (1.94%, 95% CI: ±0.55) originating from 35 villages of studied districts (7.22%, 95% CI: ±2.30). The highest prevalence was found in Attock (7.11%, 95% CI: ±3.36), followed by Lahore (4.83%, 95% CI: ±3.49), Sahiwal (4.70%, 95% CI: ±2.6), Dera Ghazi Khan (2.33%, 95% CI: ±2.02), Faisalabad (1.35%, 95% CI: ±1.18) and Sheikhupura (0.68%, 95% CI: ±0.94). The odds of detecting bacterial DNA in soil was increased with a unit increase in organic matter [2.511 (95% CI: 1.453-4.340), p=0.001] and sodium [1.013 (95% CI: 1.005-1.022), p=0.001], whereas, calcium [0.984 (95% CI: 0.975-0.994), p=0.002] and potassium [0.994 (95% CI: 0.990-0.999), p=0.011] had protective effect where a unit increase in each analyte decreased odds for its occurrence by 1.0% approximately. Likewise, for categorical variables (risk factors), the odds of detecting C. burnetii were higher at locations >500m away from a main road [1.95 (95% CI: 1.06-3.78), p=0.04]. The enzyme-linked immunosorbent assay (ELISA) revealed an increased prevalence of antibodies in sheep (17.9%, 95% CI: ±5.54) compared with goats (16.4%, 95% CI: ±4.34). When determining the association between soil DNA and C. burnetii antibodies in small ruminants, the odds of detecting these antibodies were significant in sheep at the livestock barns [2.81 (95% CI: 1.20-7.37), p=0.02]. The IS1111 gene-based sequence analysis revealed a clustering of the DNA into two distinct groups with much genetic divergence (0.76-68.70%): the first group that contained sequences from Lahore district clustered with human and buffalo origin isolates, whereas the second group that contained the sequences from the remaining study districts clustered with goat-, rodent- and human-origin isolates. This study provides the first evidence of the presence of C. burnetii in the environment in Punjab province, Pakistan. Future studies are needed to ascertain the bacteria's molecular epidemiology over a wide geographical area, type the isolates, and evaluates the potential risks to human populations, particularly farmers and veterinarians.

Intranasal Insulin Administration Ameliorates Streptozotocin (ICV)-Induced Insulin Receptor Dysfunction, Neuroinflammation, Amyloidogenesis, and Memory Impairment in Rats

Alzheimer's disease (AD) is associated with reduced insulin level and impairment of insulin receptor (IR) signaling in the brain, which correlates to amyloid pathology, neuroinflammation, and synaptic neurotoxicity. Clinical studies show that intranasal insulin improves memory in AD patients without peripheral hypoglycemia. However, neuroprotective molecular mechanism of the beneficial effect of intranasal insulin in AD pathology is unexplored. Therefore, we investigated the role of intranasal insulin on intracerebroventricular (ICV) streptozotocin (STZ)-induced memory impairment in rats as evaluated in the Morris water maze test. STZ (ICV) treated rats had shown memory impairment along with a significant decrease in IR signaling molecules (IR, pIRS-1, pAkt, and pGSK-3α/β expression) and IDE expression in both hippocampus and cerebral cortex. Intranasal insulin delivery prevented these changes. Moreover, intranasal insulin was found to inhibit significantly glial cell activation (GFAP and Iba-1 expression), neuroinflammation (COX-2 expression, NFκB translocation, TNF-α, and IL-10 level) and amyloidogenic protein expression (BACE-1 and Aβ_1-42 expression) in STZ (ICV)-injected rats. STZ (ICV)-induced caspase activation and postsynaptic neurotoxicity were also prevented by treatment with intranasal insulin. Our findings reveal that insulin has the neuroprotective effect and clearly signifies the potential use of intranasal insulin delivery for the treatment of AD. Graphical Abstract Neuroprotective effects of intranasal insulin administration on streptozotocin (ICV)-induced memory impairment in rats.

Inhibition of fatty acid synthase is protective in pulmonary hypertension

BACKGROUND AND PURPOSE

In pulmonary hypertension (PH), similar to cancer, there is altered energy metabolism, apoptosis resistance and cellular proliferation leading to pulmonary vascular remodelling. Proliferating cells exhibit higher rate of de novo fatty acid synthesis to provide lipids for membrane formation and energy production. As inhibition of de novo fatty acid synthesis proved protective in cancer experimentally, therefore, it was hypothesized that modulation of de novo fatty acid synthesis by inhibition of fatty acid synthase (FAS) may prove beneficial for PH.

EXPERIMENTAL APPROACH

For in vitro studies, human pulmonary artery smooth muscle cells (HPASMCs) were exposed to hypoxia and to induce PH in vivo, rats were treated with monocrotaline (MCT). FAS was inhibited by siRNA (60 nM) and C75 (2 mg·kg(-1) , i.p. once a week for 5 weeks) in in vitro and in vivo studies respectively.

RESULTS

Increased expression and activity of FAS were observed in hypoxic HPASMCs and lungs of MCT-treated rats. Inhibition of FAS increased apoptosis and glucose oxidation, but decreased proliferation and markers of autophagy, glycolysis and insulin resistance in hypoxic HPASMCs. It also improved the mitochondrial functions as evident by increased level of ATP and restoration of normal level of ROS and membrane potential of mitochondria. In MCT-treated rats, FAS inhibition decreased right ventricular pressure, hypertrophy, pulmonary vascular remodelling (increased apoptosis and decreased proliferation of cells) and endothelial dysfunction in lungs.

CONCLUSIONS

Our results demonstrate that FAS activity is modulated in PH, and its inhibition may provide a new therapeutic approach to treat PH.

Perindopril Attenuates Lipopolysaccharide-Induced Amyloidogenesis and Memory Impairment by Suppression of Oxidative Stress and RAGE Activation

Clinical and preclinical studies account hypertension as a risk factor for dementia. We reported earlier that angiotensin-converting enzyme (ACE) inhibition attenuated the increased vulnerability to neurodegeneration in hypertension and prevented lipopolysaccharide (LPS)-induced memory impairment in normotensive wistar rats (NWRs) and spontaneously hypertensive rats (SHRs). Recently, a receptor for advanced glycation end products (RAGE) has been reported to induce amyloid beta (Aβ1-42) deposition and memory impairment in hypertensive animals. However, the involvement of ACE in RAGE activation and amyloidogenesis in the hypertensive state is still unexplored. Therefore, in this study, we investigated the role of ACE on RAGE activation and amyloidogenesis in memory-impaired NWRs and SHRs. Memory impairment was induced by repeated (on days 1, 4, 7, and 10) intracerebroventricular (ICV) injections of LPS in SHRs (25 μg) and NWRs (50 μg). Our data showed that SHRs exhibited increased oxidative stress (increased gp91-phox/NOX-2 expression and ROS generation), RAGE, and β-secretase (BACE) expression without Aβ1-42 deposition. LPS (25 μg, ICV) further amplified oxidative stress, RAGE, and BACE activation, culminating in Aβ1-42 deposition and memory impairment in SHRs. Similar changes were observed at the higher dose of LPS (50 μg, ICV) in NWRs. Further, LPS-induced oxidative stress was associated with endothelial dysfunction and reduction in cerebral blood flow (CBF), more prominently in SHRs than in NWRs. Finally, we showed that perindopril (0.1 mg/kg, 15 days) prevented memory impairment by reducing oxidative stress, RAGE activation, amyloidogenesis, and improved CBF in both SHRs and NWRs. These findings suggest that perindopril might be used as a therapeutic strategy for the early stage of dementia.

Inhibitory Effect of Memantine on Streptozotocin-Induced Insulin Receptor Dysfunction, Neuroinflammation, Amyloidogenesis, and Neurotrophic Factor Decline in Astrocytes

Our earlier studies showed that insulin receptor (IR) dysfunction along with neuroinflammation and amyloidogenesis played a major role in streptozotocin (STZ)-induced toxicity in astrocytes. N-methyl-D-aspartate (NMDA) receptor antagonist-memantine shows beneficial effects in Alzheimer's disease (AD) pathology. However, the protective molecular and cellular mechanism of memantine in astrocytes is not properly understood. Therefore, the present study was undertaken to investigate the effect of memantine on insulin receptors, neurotrophic factors, neuroinflammation, and amyloidogenesis in STZ-treated astrocytes. STZ (100 μM) treatment for 24 h in astrocytes resulted significant decrease in brain-derived neurotrophic factor (BDNF), glial cell line-derived neurotrophic factor (GDNF), and insulin-degrading enzyme (IDE) expression in astrocytes. Treatment with memantine (1-10 μM) improved STZ-induced neurotrophic factor decline (BDNF, GDNF) along with IR dysfunction as evidenced by a significant increase in IR protein expression, phosphorylation of IRS-1, Akt, and GSK-3 α/β in astrocytes. Further, memantine attenuated STZ-induced amyloid precursor protein (APP), β-site APP-cleaving enzyme-1 and amyloid-β_1-42 expression and restored IDE expression in astrocytes. In addition, memantine also displays protective effects against STZ-induced astrocyte activation showed by reduction of inflammatory markers, nuclear factor kappa-B translocation, glial fibrillary acidic protein, cyclooxygenase-2, tumor necrosis factor-α level, and oxidative-nitrostative stress. The results suggest that besides the NMDA receptor antagonisic activity, effect on astroglial IR and neurotrophic factor may also be an important factor in the beneficial effect of memantine in AD pathology. Graphical Abstract Novel neuroprotective mechanisms of memenatine in streptozotocin-induced toxicity in astrocytes.

Sulforaphane Ameliorates Okadaic Acid-Induced Memory Impairment in Rats by Activating the Nrf2/HO-1 Antioxidant Pathway

Okadaic acid (OKA) causes memory impairment and attenuates nuclear factor erythroid 2-related factor 2 (Nrf2) along with oxidative stress and neuroinflammation in rats. Sulforaphane (dietary isothiocyanate compound), an activator of Nrf2 signaling, exhibits neuroprotective effects. However, the protective effect of sulforaphane in OKA-induced neurotoxicity remains uninvestigated. Therefore, in the present study, the role of sulforaphane in OKA-induced memory impairment in rats was explored. A significant increased Nrf2 expression in the hippocampus and cerebral cortex was observed in trained (Morris water maze) rats, and a significant decreased Nrf2 expression in memory-impaired (OKA, 200 ng icv) rats indicated its involvement in memory function. Sulforaphane administration (5 and 10 mg/kg, ip, days 1 and 2) ameliorates OKA-induced memory impairment in rats. The treatment also restored Nrf2 and its downstream antioxidant protein expression (GCLC, HO-1) and attenuated oxidative stress (ROS, nitrite, GSH), neuroinflammation (NF-κB, TNF-α, IL-10), and neuronal apoptosis in the cerebral cortex and hippocampus of OKA-treated rats. Further, to determine whether modulation of Nrf2 signaling is responsible for the protective effect of sulforaphane, in vitro, Nrf2 siRNA and its downstream HO-1 inhibition studies were carried out in a rat astrocytoma cell line (C6). The protective effects of sulforaphane were abolished with Nrf2 siRNA and HO-1 inhibition in astrocytes. The results suggest that Nrf2-dependent activation of cellular antioxidant machinery results in sulforaphane-mediated protection against OKA-induced memory impairment in rats. Graphical Abstract ᅟ.

Hypertension exacerbates predisposition to neurodegeneration and memory impairment in the presence of a neuroinflammatory stimulus: Protection by angiotensin converting enzyme inhibition

Hypertension is a risk factor for cognitive impairment. Furthermore, neuroinflammation and neurodegeneration are intricately associated with memory impairment. Therefore, the present study aimed to explore the involvement of hypertension and angiotensin system in neurodegeneration and memory dysfunction in the presence of neuroinflammatory stimulus. Memory impairment was induced by chronic neuroinflammation that was developed by repeated intracerebroventricular (ICV) injections of lipopolysaccharide (LPS) on the 1st, 4th, 7th, and 10th day. Memory functions were evaluated by the Morris water maze (MWM) test on days 13-15, followed by biochemical and molecular studies in the cortex and hippocampus regions of rat brain. LPS at the dose of 25μg ICV caused memory impairment in spontaneously hypertensive rats (SHRs) but not in normotensive Wistar rats (NWRs). Memory deficit was obtained with 50μg of LPS (ICV) in NWRs. Control SHRs already exhibited increased angiotensin converting enzyme (ACE) activity and expression, neuroinflammation (increased TNF-α, GFAP, COX-2 and NF-kB), oxidative stress (increased iNOS, ROS and nitrite levels), TLR-4 expression and TUNEL positive cells as compared to control NWRs. Further, LPS (25μg ICV) exaggerated inflammatory response, oxidative stress and apoptosis in SHRs but similar effects were witnessed at 50μg of LPS (ICV) in NWRs. Oral administration of perindopril (ACE inhibitor), at non-antihypertensive dose (0.1mg/kg), for 15days attenuated LPS induced deleterious changes in both NWRs and SHRs. Our data suggest that susceptibility of the brain for neurodegeneration and memory impairment induced by neuroinflammation is enhanced in hypertension, and that can be protected by ACE inhibition.

Withania somnifera shows a protective effect in monocrotaline-induced pulmonary hypertension

CONTEXT

Withania somnifera (Linn.) Dunal (Solanaceae), a clinically used herbal drug in Ayurveda, shows potent antioxidant, anti-inflammatory, pro-apoptotic, and cardioprotective effects. However, the efficacy of W. somnifera in pulmonary hypertension (PH), a cardiopulmonary disorder, remains unexplored.

OBJECTIVE

The present study investigates the effect of W. somnifera root powder on monocrotaline (MCT)-induced PH in rats.

MATERIALS AND METHODS

In preventive studies, W. somnifera root powder (50 and 100 mg/kg/d, p.o.) was administered from day 1 following single administration of MCT (60 mg/kg, s.c.) in Sprague-Dawley (SD) rats. After 35 d, right ventricular pressure (RVP) was measured in anesthetized rats. Various physical markers of right ventricular hypertrophy (RVH) were measured in isolated hearts. Markers of endothelial function, inflammation, and oxidative stress were estimated in lung homogenate. Vasoreactivity of pulmonary arteries was also studied. In therapeutic treatment, W. somnifera (50 and 100 mg/kg/d, p.o.) was administered from day 21 to 35 post-MCT administration.

RESULTS

Preventive treatment with 50 and 100 mg/kg W. somnifera significantly reduced the RVP (32.18 ± 1.273 mm Hg and 29.98 ± 1.119 mm Hg, respectively, versus 42.96 ± 1.789 mm Hg of MCT) and all markers of RVH in MCT-challenged rats. There was an improvement in inflammation, oxidative stress and endothelial dysfunction, and attenuation of proliferative marker and apoptotic resistance in lungs. Therapeutic treatment with W. somnifera (100 mg/kg) also reduced RVP and RVH.

DISCUSSION

This study demonstrated that W. somnifera significantly protected against MCT-induced PH due to its antioxidant, anti-inflammatory, pro-apoptotic, and cardioprotective properties.

Poly (ADP-ribose) polymerase-1: an emerging target in right ventricle dysfunction associated with pulmonary hypertension

Recently, inhibition of poly (ADP-ribose) polymerase-1 (PARP1) was shown to be protective in experimental pulmonary hypertension (PH) and prevented right ventricular hypertrophy (RVH) associated with it. However, molecular mechanism behind cardioprotection by PARP1 inhibition in PH still needs detailed exploration. Therefore, effect of inhibition of PARP1 on the right ventricle (RV) dysfunction was studied in monocrotaline (MCT) induced PH model. Following a single dose administration of MCT (60 mg/kg, s.c.), male Sprague-Dawley rats were treated with PARP1 inhibitor 1,5-Isoquinolinediol (ISO, 3 mg/kg, i.p.) for 35 days for preventive study and from day 21-35 for curative study. RV pressure (RVP) and RVH were measured after 35 days. Histophathological studies, PARP1 activity, mRNA and protein expression were studied in isolated RV. Oxidative and nitosative stress, inflammation and Matrix metalloproteinases (MMPs)/Tissue inhibitor of metalloproteinase 2 (TIMP2) were also assessed. Mitochondrial dysfunction was studied by mitochondrial membrane permeability and estimation of Nicotinamide adenine dinucleotide (NAD) and Adenosine triphosphate (ATP). Apoptosis in RV was assessed by Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL), caspase 3 activity and cleaved PARP1 expression. PARP1 inhibition significantly reversed the increase in RVP and RVH in both preventive and curative treatment in the MCT-injected rats. ISO lowered oxidative and nitrosative stress and inflammation and restored the balance of MMPs/TIMP2 expression. PARP1 inhibition prevented mitochondrial dysfunction and the release of cell death factors from mitochondria. ISO also decreased apoptosis by decreasing number of TUNEL positive cells, caspase 3 activity and PARP1 cleavage in RV. Thus, PARP1 inhibition ameliorated PH induced RV hypertrophy and may emerge as a new therapeutic target for PH.

Effect of homeopathic Lycopodium clavatum on memory functions and cerebral blood flow in memory-impaired rats

BACKGROUND

Lycopodium clavatum (Lyc) is a widely used homeopathic medicine for the liver, urinary and digestive disorders. Recently, acetyl cholinesterase (AchE) inhibitory activity has been found in Lyc alkaloid extract, which could be beneficial in dementia disorder. However, the effect of Lyc has not yet been explored in animal model of memory impairment and on cerebral blood flow.

AIM

The present study was planned to explore the effect of Lyc on learning and memory function and cerebral blood flow (CBF) in intracerebroventricularly (ICV) administered streptozotocin (STZ) induced memory impairment in rats.

MATERIALS AND METHODS

Memory deficit was induced by ICV administration of STZ (3 mg/kg) in rats on 1st and 3rd day. Male SD rats were treated with Lyc Mother Tincture (MT) 30, 200 and 1000 for 17 days. Learning and memory was evaluated by Morris water maze test on 14th, 15th and 16th day. CBF was measured by Laser Doppler flow meter on 17th day.

RESULTS

STZ (ICV) treated rats showed impairment in learning and memory along with reduced CBF. Lyc MT and 200 showed improvement in learning and memory. There was increased CBF in STZ (ICV) treated rats at all the potencies of Lyc studied.

CONCLUSION

The above study suggests that Lyc may be used as a drug of choice in condition of memory impairment due to its beneficial effect on CBF.

Protection of streptozotocin induced insulin receptor dysfunction, neuroinflammation and amyloidogenesis in astrocytes by insulin

Impaired insulin signaling, amyloid pathology and neuroinflammation are closely associated with neurodegenerative disorder like Alzheimer's disease (AD). Our earlier studies showed that intracerebroventricular streptozotocin (STZ) induces insulin receptor (IR) signaling defect in the hippocampus, which is associated with memory impairment in rats. Astrocytes are the most abundant cells in the brain and play a major role in neuroinflammation. However, involvement of astrocytes in STZ induced IR dysfunction has not received much attention. Therefore, the present study was planned to explore the effect of STZ on IR signaling, proinflammatory markers and amyloidogenesis in rat astrocytoma cell line, (C6). STZ (100 μM) treatment in astrocytes (n = 3) for 24 h, resulted significant decrease in IR mRNA and protein expression, phosphorylation of IRS-1, Akt, GSK-3α and GSK-3β (p < 0.01). Further STZ induced amyloidogenic protein expression as evidenced by the increase in APP, BACE-1 and Aβ1-42 expression (p < 0.05) in astrocytes. STZ also significantly induced astrocytes activation as evidenced by increased expression of GFAP and p-P38 MAPK (p < 0.05). STZ treatment caused enhanced translocation of p65 NF-kB, triggered over expression of TNF-α, IL-1β, COX-2, oxidative/nitrosative stress and caspase activation (p < 0.05) in astrocytes. Insulin (25-100 nM) pretreatment (n = 3) significantly prevented changes in IR signaling, amyloidogenic protein expression and levels of proinflammatory markers (p < 0.05) in STZ treated astroglial cells. In the present study, the protective effect of insulin suggests that, IR dysfunction along with amyloidogenesis and neuroinflammation may have played a major role in STZ induced toxicity in astrocytes which are relevant to AD pathology.

PARP1 during embryo implantation and its upregulation by oestradiol in mice

Pregnancy requires successful implantation of an embryo, which occurs during a restricted period defined as ‘receptivity of the endometrium’ and is influenced by the ovarian steroids progesterone and oestradiol. The role of poly(ADP-ribose)polymerase-1 (PARP1) in apoptosis is well established. However, it is also involved in cell differentiation, proliferation and tissue remodelling. Previous studies have described the presence of PARP in the uterus, but its exact role in embryo implantation is not yet elucidated. Hence, in this study, we studied the expression of PARP1 in the uterus during embryo implantation and decidualisation, and its regulation by ovarian steroids. Our results show upregulation of the native form of PARP1 (∼116 kDa) in the cytosolic and nuclear compartments of implantation and non-implantation sites at day 5 (0500 h), followed by downregulation at day 5 (1000 h), during the embryo implantation period. The transcript level of Parp1 was also augmented during day 5 (0500 h). Inhibition of PARP1 activity by the drug EB-47 decreased the number of embryo implantation sites and blastocysts at day 5 (1000 h). Further, cleavage of native PARP1 was due to the activity of caspase-3 during the peri-implantation stage (day 5 (0500 h)), and is also required for embryo implantation, as inhibition of its activity compromised blastocyst implantation. The native (∼116 kDa) and cleaved (∼89 kDa) forms of PARP1 were both elevated during decidualisation of the uterus. Furthermore, the expression level of PARP1 in the uterus was found to be under the control of the hormone oestrogen. Our results clearly demonstrate that PARP1 participates in the process of embryo implantation.

LPS induces mediators of neuroinflammation, cell proliferation, and GFAP expression in human astrocytoma cells U373MG: the anti-inflammatory and anti-proliferative effect of guggulipid

Neuroinflammation has been considered to be an integrated part of human neurodegenerative diseases. In this study, we examined the effect of guggulipid on cell proliferation, nitrite release, interleukin IL-6 and IL-1 beta release, and expression of COX-2 and glial fibrillary acidic protein (GFAP) in LPS-stimulated U373MG cells. LPS significantly stimulated human astrocytoma cells U373MG by up-regulating these neuroinflammatory mediators. Guggulipid alone had no effect on the cell proliferation of U373MG cells. The up regulation in nitrite release, cell proliferation, and release of IL-6 and IL-1 beta in LPS stimulated human astrocytoma cells were dose-dependently inhibited by co-treatment with guggulipid. The expression level of COX-2 and GFAP proteins was up regulated by LPS but the increased level of COX-2 and GFAP was significantly down regulated by treatment with guggulipid. These data indicate that guggulipid has a modulatory effect on all these parameters, which might explain its beneficial effect in the treatment of neuroinflammation-associated disorders directly relating to human aspects.

Effect of angiotensin II on spatial memory, cerebral blood flow, cholinergic neurotransmission, and brain derived neurotrophic factor in rats

RATIONAL

Studies have shown the involvement of angiotensin II (Ang II) in neurobehavioral aspects, but the exact role of Ang II in memory is still ambiguous.

OBJECTIVE

This study explored the effect of central Ang II on spatial memory along with cholinergic neurotransmission, brain energy metabolism, cerebral blood flow (CBF), and brain-derived neurotrophic factor (BDNF) in rats.

METHODS

Spatial memory was evaluated by Morris water maze (MWM) after Ang II (ICV) administration in male Sprague-Dawley rats. CBF was measured by laser Doppler flowmetry. Oxidative stress adenosine triphosphate (ATP), BDNF, acetylcholinesterase (AChE), and acetylcholine (ACh) were estimated in the cortex and hippocampus at 1, 24, and 48 h after Ang II administration. The effect of AT1 and AT2 receptor blocker (candesartan and PD123,319, respectively), AChE inhibitor (donepezil), and antioxidant melatonin was studied on memory, CBF, and biochemical parameters.

RESULTS

Ang II caused spatial memory impairment by affecting acquisition, consolidation, and recall in the MWM test along with a significant reduction in CBF. Ang II significantly reduced ACh level and caused oxidative stress in the rat brain 1 h post-injection. No significant change was observed in BDNF, AChE, and ATP level. Candesartan and donepezil prevented Ang II-induced memory impairment, reduction in CBF and ACh level. However, PD123,319 and melatonin failed to prevent Ang II-induced memory impairment but improved CBF partially.

CONCLUSION

This study suggests that Ang II, via the AT1 receptor, affects spatial memory formation, CBF, and ACh level while AT2 receptor has no significant role.

A Comparative Study of Neuroprotective Effect of Single and Combined Blockade of AT1 Receptor and PARP-1 in Focal Cerebral Ischaemia in Rat

Background

Cerebral ischaemia results in enhanced expression of type 1 angiotensin receptor and oxidative stress. Free radicals due to oxidative stress lead to excessive DNA damage causing overactivation of poly (ADP-ribose) polymerase-1 resulting in neuronal death. Activation of both type 1 angiotensin receptors and poly (ADP-ribose) polymerase-1 following cerebral ischaemia takes place simultaneously, but until now, no study has explored the effect of combined blockade of both angiotensin type 1 angiotensin receptor and poly (ADP-ribose) polymerase-1 in cerebral ischaemia.

Aim

Our purpose was to compare the effect of single and combined treatment with angiotensin type 1 angiotensin receptor blocker, candesartan, and the poly (ADP-ribose) polymerase-1 inhibitor, 1, 5 isoquinolinediol, on brain damage and oxidative stress in transient focal cerebral ischaemia in rats.

Method

Transient focal cerebral ischaemia was induced in Sprague-Dawley rats by an intraluminal technique for two-hours following 48 h of reperfusion. Candesartan (0·05 mg/kg) was administered just after initiation of ischaemia followed by a repeat administration at 24 h while 1, 5 isoquinolinediol (0·1 mg/kg) was given one-hour after of ischaemia. After 24 h of reperfusion, neurological deficit was evaluated in the different treatment groups. After 48 h of reperfusion, the rats were sacrificed and the brain was isolated. Ischaemic brain damage by 2,3,5 triphenyl tetrazolium chloride staining, oxidative stress markers, and levels of reactive oxygen species were determined biochemically.

Result

Single treatment with candesartan and 1, 5 isoquinolinediol significantly reduced neurological deficit, infarct, and oedema volume as compared to ischaemic control and different vehicle groups for each of the drugs. However, treatment with candesartan + 1, 5 isoquinolinediol offered greater reduction in neurological deficit, cerebral infarct volume, and oedema as compared to single-drug treatments. Furthermore, treatment with candesartan + 1, 5 isoquinolinediol significantly decreased oxidative stress as compared to single treatments with each drug.

Conclusion

The study suggests that blockade of either type 1 angiotensin receptor or poly (ADP-ribose) polymerase-1 alone provides neuroprotection, but the better result was achieved when both type 1 angiotensin receptor and poly (ADP-ribose) polymerase-1 were blocked together by the combined use of their pharmacological inhibitor in transient cerebral ischaemia in rat.

Role of central angiotensin receptors in scopolamine-induced impairment in memory, cerebral blood flow, and cholinergic function

RATIONAL

Inhibition of renin-angiotensin system (RAS) improves cognitive functions in hypertensive patients. However, role of AT1 and AT2 receptors in memory impairment due to cholinergic hypofunction is unexplored.

OBJECTIVE

This study investigated the role of AT1 and AT2 receptors in cerebral blood flow (CBF), cholinergic neurotransmission, and cerebral energy metabolism in scopolamine-induced amnesic mice.

METHODS

Scopolamine was given to male Swiss albino mice to induce memory impairment tested in passive avoidance and Morris water maze tests after a week long administration of blocker of AT1 receptor, candesartan, and AT2 receptor, PD123, 319. CBF was measured by laser Doppler flowmetry. Biochemical and molecular studies were done in cortex and hippocampus of mice brain.

RESULTS

Scopolamine caused memory impairment, reduced CBF, acetylcholine (ACh) level, elevated acetylcholinesterase (AChE) activity, and malondialdehyde (MDA). Administration of vehicle had no significant effect on any parameter in comparison to control. Candesartan prevented scopolamine-induced amnesia, restored CBF and ACh level, and decreased AChE activity and MDA level. In contrast, PD123, 319 was not effective. However, the effect of AT1 receptor blocker on memory, CBF, ACh level, and oxidative stress was blunted by concomitant blockade of AT2 receptor. Angiotensin-converting enzyme (ACE) activity, ATP level, and mRNA expression of AT1, AT2, and ACE remained unaltered.

CONCLUSION

The study suggests that activation of AT1 receptors appears to be involved in the scopolamine-induced amnesia and that AT2 receptors contribute to the beneficial effects of candesartan. Theses finding corroborated the number of clinical studies that RAS inhibition in hypertensive patients could be neuroprotective.

Inhibition of central angiotensin converting enzyme ameliorates scopolamine induced memory impairment in mice: role of cholinergic neurotransmission, cerebral blood flow and brain energy metabolism

Evidences indicate that inhibition of central Renin angiotensin system (RAS) ameliorates memory impairment in animals and humans. Earlier we have reported involvement of central angiotensin converting enzyme (ACE) in streptozotocin induced neurodegeneration and memory impairment. The present study investigated the role of central ACE in cholinergic neurotransmission, brain energy metabolism and cerebral blood flow (CBF) in model of memory impairment induced by injection of scopolamine in mice. Perindopril (0.05 and 0.1 mg/kg, PO) was given orally for one week before administration of scopolamine (3mg/kg, IP). Then, memory function was evaluated by Morris water maze and passive avoidance tests. CBF was measured by laser Doppler flowmetry. Biochemical and molecular parameters were estimated after the completion of behavioral studies. Scopolamine caused impairment in memory which was associated with reduced CBF, acetylcholine (ACh) level and elevated acetylcholinesterase (AChE) activity and malondialdehyde (MDA) level. Perindopril ameliorated scopolamine induced amnesia in both the behavioral paradigms. Further, perindopril prevented elevation of AChE and MDA level in mice brain. There was a significant increase in CBF and ACh level in perindopril treated mice. However, scopolamine had no significant effect on ATP level and mRNA expression of angiotensin receptors and ACE in cortex and hippocampus. But, perindopril significantly decreased ACE activity in brain without affecting its mRNA expression. The study clearly showed the interaction between ACE and cholinergic neurotransmission and beneficial effect of perindopril can be attributed to improvement in central cholinergic neurotransmission and CBF.