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Traumatic brain injury (TBI) is a major cause of disability and death. Mild TBI (mTBI) constitutes ~75% of all TBI cases. Repeated exposure to mTBI (rmTBI), leads to the exacerbation of the symptoms compared to single mTBI. To date, there is no FDA-approved drug for TBI or rmTBI. This research aims to investigate possible rmTBI neurotherapy by targeting TBI pathology-related mechanisms. Oxidative stress is partly responsible for TBI/rmTBI neuropathologic outcomes. Thus, targeting oxidative stress may ameliorate TBI/rmTBI consequences. In this study, we hypothesized that mitoquinone (MitoQ), a mitochondria-targeted antioxidant, would ameliorate TBI/rmTBI associated pathologic features by mitigating rmTBI-induced oxidative stress. To model rmTBI, C57BL/6 mice were subjected to three concussive head injuries. MitoQ (5 mg/kg) was administered intraperitoneally to rmTBI+MitoQ mice twice per week over one month. Behavioral and cognitive outcomes were assessed, 30 days following the first head injury, using a battery of behavioral tests. Immunofluorescence was used to assess neuroinflammation and neuronal integrity. Also, qRT-PCR was used to evaluate the expression levels of antioxidant enzymes. Our findings indicated that MitoQ alleviated fine motor function and learning impairments caused by rmTBI. Mechanistically, MitoQ reduced astrocytosis, microgliosis, dendritic and axonal shearing, and increased the expression of antioxidant enzymes. MitoQ administration following rmTBI may represent an efficient approach to ameliorate rmTBI neurological and cellular outcomes with no observable side effects., (Copyright © 2022. Published by Elsevier Inc.)

We managed to repurpose the old drug iodoquinol to a series of novel anticancer 7-iodo-quinoline-5,8-diones. Twelve compounds were identified as inhibitors of moderate to high potency on an inhouse MCF-7 cell line, of which 2 compounds (5 and 6) were capable of reducing NAD level in MCF-7 cells in concentrations equivalent to half of their IC 50 s, potentially due to NAD(P)H quinone oxidoreductase (NQO1) inhibition. The same 2 compounds (5 and 6) were capable of reducing p53 expression and increasing reactive oxygen species levels, which further supports the NQO-1 inhibitory activity. Furthermore, 4 compounds (compounds 5-7 and 10) were qualified by the Development Therapeutic Program (DTP) division of the National Cancer Institute (NCI) for full panel five-dose in vitro assay to determine their GI 50 on the 60 cell lines. All five compounds showed broad spectrum sub-micromolar to single digit micromolar GI 50 against a wide range of cell lines. Cell cycle analysis and dual staining assays with annexin V-FITC/propidium iodide on MCF-7 cells confirmed the capability of the most active compound (compound 5) to induce cell cycle arrest at Pre-G1 and G2/M phases as well as apoptosis. Both cell cycle arrest and apoptosis were affirmed at the molecular level by the ability of compound 5 to enhance the expression levels of caspase-3 and Bax together with suppressing that of CDK1 and Bcl-2. Additionally, an anti-angiogenic effect was evident with compound 5 as supported by the decreased expression of VEGF. Interesting binding modes within NQO-1 active site had been identified and confirmed by both molecular docking and dymanic experiments., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Blood pressure (BP) varies on the long, short and very-short term. Owing to the hidden physiological and pathological information present in BP time-series, increasing interest has been given to the study of continuous, beat-to-beat BP variability (BPV) using invasive and noninvasive methods. Different linear and nonlinear parameters of variability are employed in the characterization of BP signals in health and disease. Although linear parameters of beat-to-beat BPV are mainly measures of dispersion, such as standard deviation (SD), nonlinear parameters of BPV quantify the degree of complexity/irregularity- using measures of entropy or self-similarity/correlation. In this review, we summarize the value of linear and nonlinear parameters in reflecting different information about the pathophysiology of changes in beat-to-beat BPV independent of or superior to mean BP. We then provide a comparison of the relative power of linear and nonlinear parameters of beat-to-beat BPV in detecting early and subtle differences in various states. The practical advantage and utility of beat-to-beat BPV monitoring support its incorporation into routine clinical practices., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Diabetic nephropathy is a major health challenge with considerable economic burden and significant impact on patients' quality of life. Despite recent advances in diabetic patient care, current clinical practice guidelines fall short of halting the progression of diabetic nephropathy to end-stage renal disease. Moreover, prior literature reported manifestations of renal dysfunction in early stages of metabolic impairment prior to the development of hyperglycemia indicating the involvement of alternative pathological mechanisms apart from those typically triggered by high blood glucose. Here, we extend our prior research work implicating localized inflammation in specific adipose depots in initiating cardiovascular dysfunction in early stages of metabolic impairment. Non-obese prediabetic rats showed elevated glomerular filtration rates and mild proteinuria in absence of hyperglycemia, hypertension, and signs of systemic inflammation. Isolated perfused kidneys from these rats showed impaired renovascular endothelial feedback in response to vasopressors and increased flow. While endothelium dependent dilation remained functional, renovascular relaxation in prediabetic rats was not mediated by nitric oxide and prostaglandins as in control tissues, but rather an upregulation of the function of epoxy eicosatrienoic acids was observed. This was coupled with signs of peri-renal adipose tissue (PRAT) inflammation and renal structural damage. A two-week treatment with non-hypoglycemic doses of metformin or pioglitazone, shown previously to ameliorate adipose inflammation, not only reversed PRAT inflammation in prediabetic rats, but also reversed the observed functional, renovascular, and structural renal abnormalities. The present results suggest that peri-renal adipose inflammation triggers renal dysfunction early in the course of metabolic disease., (Copyright © 2021 Elsevier Inc. All rights reserved.)

ACE2 has emerged as a double agent in the COVID-19 ordeal, as it is both physiologically protective and virally conducive. The identification of ACE2 in as many as 72 tissues suggests that extrapulmonary invasion and damage is likely, which indeed has already been demonstrated by cardiovascular and gastrointestinal symptoms. On the other hand, identifying ACE2 dysregulation in patients with comorbidities may offer insight as to why COVID-19 symptoms are often more severe in these individuals. This may be attributed to a pre-existing proinflammatory state that is further propelled with the cytokine storm induced by SARS-CoV-2 infection or the loss of functional ACE2 expression as a result of viral internalization. Here, we aim to characterize the distribution and role of ACE2 in various organs to highlight the scope of damage that may arise upon SARS-CoV-2 invasion. Furthermore, by examining the disruption of ACE2 in several comorbid diseases, we offer insight into potential causes of increased severity of COVID-19 symptoms in certain individuals. SIGNIFICANCE STATEMENT: Cell surface expression of ACE2 determines the tissue susceptibility for coronavirus infectious disease 2019 infection. Comorbid disease conditions altering ACE2 expression could increase the patient's vulnerability for the disease and its complications, either directly, through modulation of viral infection, or indirectly, through alteration of inflammatory status., (Copyright © 2020 by The American Society for Pharmacology and Experimental Therapeutics.)

Cardiac autonomic neuropathy (CAN) is an early cardiovascular manifestation of type 2 diabetes (T2D) that constitutes an independent risk factor for cardiovascular mortality and morbidity. Nevertheless, its underlying pathophysiology remains poorly understood. We recently showed that localized perivascular adipose tissue (PVAT) inflammation underlies the incidence of parasympathetic CAN in prediabetes. Here, we extend our investigation to provide a mechanistic framework for the evolution of autonomic impairment as the metabolic insult worsens. Early metabolic dysfunction was induced in rats fed a mild hypercaloric diet. Two low-dose streptozotocin injections were used to evoke a state of late decompensated T2D. Cardiac autonomic function was assessed by invasive measurement of baroreflex sensitivity using the vasoactive method. Progression into T2D was associated with aggravation of CAN to include both sympathetic and parasympathetic arms. Unlike prediabetic rats, T2D rats showed markers of brainstem neuronal injury and inflammation as well as increased serum levels of IL-1β. Experiments on PC12 cells differentiated into sympathetic-like neurons demonstrated that brainstem injury observed in T2D rats resulted from exposure to possible proinflammatory mediators in rat serum rather than a direct effect of the altered metabolic profile. CAN and the associated cardiovascular damage in T2D only responded to combined treatment with insulin to manage hyperglycemia in addition to a nonhypoglycemic dose of metformin or pioglitazone providing an anti-inflammatory effect, coincident with the effect of these combinations on serum IL-1β. Our present results indicate that CAN worsening upon progression to T2D involves brainstem inflammatory changes likely triggered by systemic inflammation.

Traumatic brain injury (TBI) is a global health burden and a major cause of disability and mortality. An early cascade of physical and structural damaging events starts immediately post-TBI. This primary injury event initiates a series of neuropathological molecular and biochemical secondary injury sequelae, that last much longer and involve disruption of cerebral metabolism, mitochondrial dysfunction, oxidative stress, neuroinflammation, and can lead to neuronal damage and death. Coupled to these events, recent studies have shown that lifestyle factors, including diet, constitute additional risk affecting TBI consequences and neuropathophysiological outcomes. There exists molecular cross-talk among the pathways involved in neuronal survival, neuroinflammation, and behavioral outcomes, that are shared among western diet (WD) intake and TBI pathophysiology. As such, poor dietary intake would be expected to exacerbate the secondary damage in TBI. Hence, the aim of this review is to discuss the pathophysiological consequences of WD that can lead to the exacerbation of TBI outcomes. We dissect the role of mitochondrial dysfunction, oxidative stress, neuroinflammation, and neuronal injury in this context. We show that currently available data conclude that intake of a diet saturated in fats, pre- or post-TBI, aggravates TBI, precludes recovery from brain trauma, and reduces the response to treatment., Competing Interests: Declaration of Competing Interest The authors declare that there are no conflicts of interest., (Copyright © 2020 The Author(s). Published by Elsevier B.V. All rights reserved.)

The onset of vascular impairment precedes that of diagnostic hyperglycemia in diabetic patients suggesting a vascular insult early in the course of metabolic dysfunction without a well-defined mechanism. Mounting evidence implicates adipose inflammation in the pathogenesis of insulin resistance and diabetes. It is not certain whether amelioration of adipose inflammation is sufficient to preclude vascular dysfunction in early stages of metabolic disease. Recent findings suggest that antidiabetic drugs, metformin, and pioglitazone, improve vascular function in prediabetic patients, without an indication if this protective effect is mediated by reduction of adipose inflammation. Here, we used a prediabetic rat model with delayed development of hyperglycemia to study the effect of metformin or pioglitazone on adipose inflammation and vascular function. At the end of the metabolic challenge, these rats were neither obese, hypertensive, nor hyperglycemic. However, they showed increased pressor responses to phenylephrine and augmented aortic and mesenteric contraction. Vascular tissues from prediabetic rats showed increased Rho-associated kinase activity causing enhanced calcium sensitization. An elevated level of reactive oxygen species was seen in aortic tissues together with increased Transforming growth factor β1 and Interleukin-1β expression. Although, no signs of systemic inflammation were detected, perivascular adipose inflammation was observed. Adipocyte hypertrophy, increased macrophage infiltration, and elevated Transforming growth factor β1 and Interleukin-1β mRNA levels were seen. Two-week treatment with metformin or pioglitazone or switching to normal chow ameliorated adipose inflammation and vascular dysfunction. Localized perivascular adipose inflammation is sufficient to trigger vascular dysfunction early in the course of diabetes. Interfering with this inflammatory process reverses this early abnormality., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Neuroinflammation and cholinergic deficit are key detrimental processes involved in Alzheimer's disease. Hence, in the search for novel and effective treatment strategies, the multi-target-directed ligand paradigm was applied to the rational design of two series of new hybrids endowed with anti-inflammatory and anticholinesterase activity via triple targeting properties, namely able to simultaneously hit cholinesterases, cyclooxygenase-2 (COX-2) and 15-lipoxygenase (15-LOX) enzymes. Among the synthesized compounds, triazoles 5b and 5d, and thiosemicarbazide hybrid 6e emerged as promising new hits, being able to effectively inhibit human butyrylcholinesterase (hBChE), COX-2 and 15-LOX enzymes with a higher inhibitory potency than the reference inhibitors tacrine (for hBChE inhibition), celecoxib (for COX-2 inhibition) and both NDGA and Zileuton (for 15-LOX inhibition). In addition, compound 6e proved to be a submicromolar mixed-type inhibitor of human acetylcholinesterase (hAChE). The anti-neuroinflammatory activity of the three most promising hybrids was confirmed in a cell-based assay using PC12 neuron cells, showing decreased expression levels of inflammatory cytokines IL-1β and TNF-α. Importantly, despite the structural resemblance to tacrine, they showed ideal safety profiles on hepatic and murine brain cell lines and were safe up to 100 μM when assayed in PC12 cells. All three hybrids were also predicted to have superior BBB permeability than tacrine in the PAMPA assay, and good physicochemical properties, drug-likeness and ligand efficiency indices. Finally, molecular docking studies highlighted key structural elements impacting selectivity and activity toward the selected target enzymes. To the best of our knowledge, compounds 5b, 5d and 6e are the first balanced, safe and multi-target compounds hitting the disease at the three mentioned hubs., (Copyright © 2019 Elsevier Masson SAS. All rights reserved.)

Over the past three decades, our view of the endothelium rapidly evolved from a static lining of the blood vessels to a dynamic determinant and regulator of vascular tone and homeostasis. It is now widely accepted that endothelial dysfunction is a hallmark of almost every vascular pathology, either as a cause or a consequence. The tight association between the metabolic disease spectrum, ranging from mild alterations of blood lipids profile all the way to diabetes and morbid obesity; and vascular complications argues for a deleterious endothelial remodeling in these conditions. Extensive research demonstrated endothelial changes in these conditions including reduced endothelial nitric oxide activity, altered response to endothelium-dependent hyperpolarization, and increased production of contractile agents. For the most part, studies investigated different aspects of endothelial function in isolation of each other. In this review, we propose a model of an integrated endothelial response and offer an alternative view for potential dysfunction early in the course of metabolic disease continuum. In such a framework, only slight changes in the expression/function of molecular players in one endothelium-dependent pathway would be sufficient to trigger a cascade of events compromising endothelial function. We will also consider the available data describing the possible effects of intervention with different therapeutic agents on endothelial function early in the course of metabolic disease., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

In search for effective multi-targeting drug ligands (MTDLs) to address low-grade inflammatory changes of metabolic disorders, we rationally designed some novel glitazones-like compounds. This was achieved by incorporating prominent pharmacophoric motifs from previously reported COX-2, 15-LOX and PPARγ ligands. Challenging our design with pre-synthetic docking experiments on PPARγ showed encouraging results. In vitro tests have identified 4 compounds as simultaneous partial PPARγ agonist, potent COX-2 antagonist (nanomolar IC 50 values) and moderate 15-LOX inhibitor (micromolar IC 50 values). We envisioned such outcome as a prototypical balanced modulation of the 3 inflammatory targets. In vitro glucose uptake assay defined six compounds as insulin-sensitive and the other two as insulin-independent glucose uptake enhancers. Also, they were able to induce PPARγ nuclear translocation in immunohistochemical analysis. Their anti-inflammatory potential has been translated to effective inhibition of monocyte to macrophage differentiation, suppression of LPS-induced inflammatory cytokine production in macrophages, as well as significant in vivo anti-inflammatory activity. Ligand co-crystallized PPARγ X-ray of one of MTDLs has identified new clues that could serve as structural basis for its partial agonism. Docking of the most active compounds into COX-2 and 15-LOX active sites, pinpointed favorable binding patterns, similar to those of the co-crystallized ligands. Finally, in silico assessment of pharmacokinetics, physicochemical properties, drug-likeness and ligand efficiency indices was performed. Hence, we anticipate that the prominent biological profile of such series will rationalize relevant anti-inflammatory drug development endeavors., (Copyright © 2019 Elsevier Masson SAS. All rights reserved.)

We recently reported that exposure to cyclosporine (CSA) plus diclofenac causes hypertension and impairs left ventricular (LV) and cardiac autonomic functions in female rats. Here, we tested the hypothesis that these effects could be mitigated by facilitated heme oxygenase (HO) signaling. Experiments were performed in female rats to assess the effects of 10-day treatment with CSA (25 mg/kg/day)/diclofenac (1 mg/kg/day) regimen on cardiovascular functions in absence and presence of maneuvers that upregulate HO or its enzymatic products. The CSA/diclofenac-induced hypertension and impairment in cardiac sympathovagal balance (i.e. reduced low-frequency/high-frequency spectral ratio) were blunted upon concurrent treatment with hemin (HO-1 inducer), tricarbonyldichlororuthenium (II) dimer (CORM-2, carbon monoxide-releasing molecule), or bilirubin. While none of the latter treatments affected the CSA/diclofenac-evoked decrease in isovolumic relaxation constant (Tau, a measure of diastolic function), the increased LV contractility (dP/dt max ) and attenuated reflex bradycardia in CSA/diclofenac-treated rats was abolished by bilirubin only. Paradoxically, the CSA/diclofenac-evoked attenuation in reflex tachycardia was improved in presence of hemin or CORM-2, but not bilirubin. The favorable hemin effects were abrogated after inhibition of HO (ZnPP) or nitric oxide synthase (NOS, l-NAME). These finding highlights NOS-dependent modulatory roles for HO and its enzymatic products in improving the worsened cardiovascular profile in CSA/diclofenac-treated female rats., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

Cyclosporine, the prototype calcineurin inhibitor, transformed immunosuppressant regimens and practices post-organ transplantation. Therapeutic uses of cyclosporine branched out to include management of different autoimmune disorders. However, multiple additional effects posed significant clinical challenges in face of the prolonged nature of cyclosporine use. Significantly, cyclosporine produced nephrotoxic, cardiotoxic and neurotoxic effects in addition to alteration of hemodynamic function. These adverse effects are shared with other drug groups further complicating the therapeutic situation to include potential exacerbation in case of drug interactions. The potential for detrimental outcomes increases with commonly used drugs such as non-steroidal anti-inflammatory drugs also notorious for their deleterious renal and cardiovascular effects. Herein, we review the available experimental and clinical evidence describing the mechanisms and the outcomes of interactions between the two drug classes. Special attention is given to the divergent toxic effects of co-administration of cyclosporine with selective vs. non-selective cyclooxygenase inhibiting non-steroidal drugs., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Click chemistry was used to synthesize a new series of thioquinazolinone molecules equipped with propargyl moiety,1,2,3-triazolyl and isoxazolyl rings. Our design was based on merging pharmacophores previously reported to exhibit COX-2 inhibitory activities to a thioquinazolinone-privileged scaffold. The synthesized compounds were subjected to in vitro cyclooxygenase COX-1/COX-2 and 15-LOX inhibition assays. Compounds 2c, 3b, 3h, 3j, and 3k showed COX-2 inhibition with IC 50 (μM) 0.18, 0.19, 0.11, 0.16 and 0.17 respectively. These values were compared to celecoxib (IC 50 0.05 μM), diclofenac (IC 50 0.8 μM) and indomethacin (IC 50 0.49 μM) reference drugs. They also showed 15-LOX inhibition with IC 50 (μM) 6.21, 4.33, 7.62, 5.21 and 3.98 respectively. These values were compared with Zileuton (IC 50 2.41 μM) and Meclofenamate sodium (IC 50 5.64 μM) as positive controls. These compounds were further challenged by PMA-induced THP-1 differentiation assay where compounds 2c and 3j inhibited monocyte to macrophage differentiation efficiently with IC 50 values of 4.78 μM and 5.63 μM, respectively, compared to that of diclofenac sodium (4.86 μM). On the other hand, 3h demonstrated a significantly increased potency compared to diclofenac in this assay (IC 50  = 0.13 μM). The same compounds exhibited significant in vivo anti-inflammatory effect as indicated by the formalin-induced rat-paw edema test. Docking experiments of compounds 2c, 3b, 3h, 3j, and 3k into COX-2 binding pocket have been conducted, where strong binding interactions have been identified and effective overall docking scores have been recorded. Their drug-likeness has been assessed using Molinspiration, Molsoft and Pre-ADMET software products., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)

Aims: The hypertensive effect of the immunosuppressant drug cyclosporine (CSA) is paralleled, and probably triggered, by impaired arterial baroreceptor sensitivity (BRS). Here we asked if these effects of CSA are influenced by co-administration of nonsteroidal antiinflammatory drugs (NSAIDs) and if the oxidative NADPH-oxidase (NADPHox)/Rho-kinase (ROCK) pathway mediates this interaction., Materials and Methods: Female rats were treated for 10days with CSA (25mg/kg/day), diclofenac (DIC, COX-1/COX-2 inhibitor, 1mg/kg/day), celecoxib (COX-2 inhibitor, 10mg/kg/day), or their combinations. Baroreflex curves relating changes in heart rate (HR) to increases or decreases in blood pressure (BP) evoked by phenylephrine (PE) and sodium nitroprusside (SNP), respectively, were constructed and slopes of the curves were taken as measures of BRS., Key Findings: Compared with control rats, CSA increased BP and reduced reflex chronotropic responses as indicated by the significantly smaller BRS PE and BRS SNP values. Similar effects were observed in rats treated with diclofenac alone or combined with CSA. Whereas CSA hypertension was maintained after selective COX-2 inhibition by celecoxib, the concomitant BRS reductions were largely eliminated. NADPHox inhibition by diphenyleneiodonium (DPI) blunted the CSA/DIC-evoked increases and decreases in BP and BRS PE , respectively. By contrast, fasudil (ROCK inhibitor) had no effect on CSA/DIC hypertension but reversed the associated reductions in both BRS PE and BRS SNP ., Significance: Depending on the nature of the cardiovascular response, NADPHox and ROCK contribute variably to the worsened cardiovascular profile in CSA/DIC-treated rats. Further, celecoxib rather than diclofenac could be a better choice as an add-on therapy to CSA in autoimmune arthritic conditions., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Cyclosporine (CSA) and nonsteroidal antiinflammatory drugs (NSAIDs) are used together to manage arthritic disorders with an immune component. Previous reports showed contrasting effects for NSAIDs on CSA nephrotoxicity and acute elevations in blood pressure. Both effects were ameliorated or exaggerated after selective cyclooxygenase-2 (COX2) and nonselective COX inhibition, respectively. Here we investigated: (i) the interaction of CSA with NSAIDs possessing variable COX1/COX2 selectivities on hemodynamic, left ventricular (LV) and cardiac autonomic and histologic profiles, and (ii) role of NADPH-oxidase (NOX)/Rho-kinase (ROCK) pathway in the interaction. Female rats were pre-instrumented with femoral catheters and treated for 10 days with CSA (25mg/kg/day), diclofenac (nonselective NSAIDs, 1mg/kg/day), celecoxib (COX2 inhibitor, 10mg/kg/day), or their combinations. CSA-mediated hypertension was maintained upon co-administration of either NSAID whereas the concomitant reductions in time- and frequency-domain indices of heart rate variability (HRV) were accentuated in presence of diclofenac but not celecoxib. The isovolumic relaxation time (Τau), a measure of diastolic function, was reduced by all regimens whereas LV contractility (dP/dt max ) remained unaffected. The CSA/diclofenac regimen, but not individual treatments, increased cardiac NOX2 expression and caused more cardiac structural damage. The inhibition of NOX by diphenyleneiodonium reversed CSA/diclofenac-evoked increases in MAP, decreases in HRV and Tau, cardiac structural damage, and increased NOX2 expression. No such effects were observed after ROCK inhibition by fasudil, despite concomitant decreases in NOX2 expression. In conclusion, CSA/diclofenac-treated female rats exhibit exacerbated hemodynamic, autonomic, LV, and histopathologic disturbances via ROCK-independent NOX2 upregulation., (Copyright © 2017 Elsevier B.V. All rights reserved.)