Resveratrol Targeting of Carcinogen-Induced Brain Endothelial Cell Inflammation Biomarkers MMP-9 and COX-2 is Sirt1-Independent

From Microcirculation to Aging-Related Diseases: A Focus on Endothelial SIRT1

Silent information regulator sirtuin 1 (SIRT1) is an NAD+-dependent deacetylase with potent anti-arterial aging activities. Its protective function in aging-related diseases has been extensively studied. In the microcirculation, SIRT1 plays a crucial role in preventing microcirculatory endothelial senescence by suppressing inflammation and oxidative stress while promoting mitochondrial function and optimizing autophagy. It suppresses hypoxia-inducible factor-1α (HIF-1α)-mediated pathological angiogenesis while promoting healthy, physiological capillarization. As a result, SIRT1 protects against microvascular dysfunction, such as diabetic microangiopathy, while enhancing exercise-induced skeletal muscle capillarization and energy metabolism. In the brain, SIRT1 upregulates tight junction proteins and strengthens their interactions, thus maintaining the integrity of the blood-brain barrier. The present review summarizes recent findings on the regulation of microvascular function by SIRT1, the underlying mechanisms, and various approaches to modulate SIRT1 activity in microcirculation. The importance of SIRT1 as a molecular target in aging-related diseases, such as diabetic retinopathy and stroke, is underscored, along with the need for more clinical evidence to support SIRT1 modulation in the microcirculation.

Design, synthesis, and antitumor mechanism investigation of iridium(III) complexes conjugated with ibuprofen

The design and synthesis of a series of metal complexes formed by non-steroidal anti-inflammatory drugs (NSAIDs) ibuprofen (IBP) and iridium(III), with the molecular formula [Ir(C^N)2bpy(4-CH2OIBP-4'-CH2OIBP)](PF6) (Ir-IBP-1, Ir-IBP-2) (C^N = 2-phenylpyridine (ppy, Ir-IBP-1), 2-(2-thienyl)pyridine (thpy, Ir-IBP-2)) was introduced in this article. Firstly, it was found that the anti-proliferative activity of these complexes was more effective than that of cisplatin. Further research showed that Ir-IBP-1 and Ir-IBP-2 can accumulate in intracellular mitochondria, thereby disrupting mitochondrial membrane potential (MMP), increasing intracellular reactive oxygen species (ROS), blocking the G2/M phase of the cell cycle, and inducing cell apoptosis. In terms of protein expression, the expression of COX-2, MMP-9, NLRP3 and Caspase-1 proteins can be downregulated, indicating their ability to anti-inflammatory and overcome immune evasion. Furthermore, Ir-IBP-1 and Ir-IBP-2 can induce immunogenic cell death (ICD) by triggering the release of cell surface calreticulin (CRT), high mobility group box 1 (HMGB1) and adenosine triphosphate (ATP). Overall, iridium(III)-IBP conjugates exhibit various anti-tumor mechanisms, including mitochondrial damage, cell cycle arrest, inflammatory suppression, and induction of ICD.

Anti-Cancer Properties of Resveratrol: A Focus on Its Impact on Mitochondrial Functions

Cancer is one of the most serious public health issues worldwide, demanding ongoing efforts to find novel therapeutic agents and approaches. Amid growing interest in the oncological applications of phytochemicals, particularly polyphenols, resveratrol-a naturally occurring polyphenolic stilbene derivative-has emerged as a candidate of interest. This review analyzes the pleiotropic anti-cancer effects of resveratrol, including its modulation of apoptotic pathways, cell cycle regulation, inflammation, angiogenesis, and metastasis, its interaction with cancer stem cells and the tumor microenvironment. The effects of resveratrol on mitochondrial functions, which are crucial to cancer development, are also discussed. Future research directions are identified, including the elucidation of specific molecular targets, to facilitate the clinical translation of resveratrol in cancer prevention and therapy.

A series of ligustrazine platinum(IV) complexes with potent anti-proliferative and anti-metastatic properties that exert chemotherapeutic and immunotherapeutic effects

The development of novel anticancer drugs with antiproliferative and antimetastatic activities is of great importance in the pharmaceutical field. Herein, a series of ligustrazine (LSZ) platinum(IV) complexes with chemotherapeutic and immunotherapeutic effects were designed, prepared and evaluated as antitumor agents for the first time. Complex 4 with potent antitumor activities both in vitro and in vivo was screened out as a candidate. Notably, it displays significantly more effective anti-metastatic activities than the platinum(II) drugs cisplatin and oxaliplatin. Mechanism detection discloses that it causes serious DNA damage and increases the expression of γ-H2AX and P53. Then, the apoptosis of tumor cells is promoted by activating the mitochondrial apoptotic pathway Bcl-2/Bax/caspase-3 and causing autophagy via modulating LC3-I/II and P62 expression. Furthermore, the immune therapeutic responses are significantly elevated by blocking HIF-1α, ERK 1/2 and COX-2 pathways to reduce PD-L1 expression, and further increasing CD3+ and CD8+ T cells to elevate T cell immunity in tumors. Tumor metastasis is blocked by the synergistic functions of DNA damage, hypoxia modulation and immune activation.

Quercetin and resveratrol ameliorate nickel-mediated hypercontraction in isolated Wistar rat aorta

PURPOSE

The ameliorative potential of quercetin and resveratrol on isolated endothelium-intact aortic rings incubated with nickel was examined.

METHOD

The effect of varying concentrations of quercetin and resveratrol was investigated on isolated Wistar rat aortic rings using an organ bath system over vasoconstrictor phenylephrine (PE) at 1 µM. To delineate the mechanism of action, isolated aortic rings were pre-incubated with pharmacological modulators, such as verapamil 1 µM, apocynin 100 µM, indomethacin 100 µM or N-G-nitro-L-arginine methyl ester (L-NAME) 100 µM, separately, before incubation with 100 µM quercetin and 30 µM resveratrol. To assess the ameliorative and prophylactic potentials of quercetin and resveratrol, aortic rings were also incubated with quercetin or resveratrol for 40 min, followed by incubation with nickel for 40 min.

RESULTS

At 100 µM, quercetin caused 29% inhibition of contraction, while resveratrol at 30 µM caused 55% inhibition of contraction in aortic rings compared with control. Aortic rings incubated with contractile modulators, such as verapamil, apocynin, indomethacin or N-G-nitro-L-arginine methyl ester (L-NAME), along with quercetin or resveratrol at their concentrations producing maximum relaxant effect, showed that both of these natural compounds exert their relaxant effect by inhibiting the generation of reactive oxygen species (ROS) from endothelial and smooth muscle cells, blocking voltage-gated calcium channels, and increasing the release of nitric oxide (NO). The mediation of hypercontraction by nickel is due to the increased ROS and the influx of calcium through voltage-dependent calcium channels. These natural compounds are shown to counter the nickel-induced effects, appearing as effective ameliorators.

CONCLUSION

In this study, we found that quercetin and resveratrol act as ameliorators of nickel-mediated hypercontraction by decreasing ROS and enhancing NO release from endothelial cells.

Ketoprofen and Loxoprofen Platinum(IV) Complexes Displaying Antimetastatic Activities by Inducing DNA Damage, Inflammation Suppression, and Enhanced Immune Response

Metastasis is a major contributor of death in cancer patients, and there is an urgent need for effective treatments of metastatic malignancies. Herein, ketoprofen (KP) and loxoprofen (LP) platinum(IV) complexes with antiproliferative and antimetastatic properties were designed and prepared by integrating chemotherapy and immunotherapy targeting cyclooxygenase-2 (COX-2), matrix metalloproteinase-9 (MMP-9), and programmed death ligand 1 (PD-L1), besides DNA. A mono-KP platinum(IV) complex with a cisplatin core is screened out as a candidate possessing potent anti-proliferative and anti-metastasis activities both in vitro and in vivo. It induces serious DNA damage and further leads to high expression of γ-H2AX and p53. Moreover, it promotes apoptosis of tumor cells through mitochondrial apoptotic pathway Bcl-2/Bax/caspase3. Then, COX-2, MMP-9, NLRP3, and caspase1 as pivotal enzymes igniting inflammation and metastasis are obviously inhibited. Notably, it significantly improves immune response through restraining the expression of PD-L1 to increase CD3⁺ and CD8⁺ T infiltrating cells in tumor tissues.

Resveratrol-Induced Signal Transduction in Wound Healing

Resveratrol is a well-known polyphenol that harbors various health benefits. Besides its well-known anti-oxidative potential, resveratrol exerts anti-inflammatory, pro-angiogenic, and cell-protective effects. It seems to be a promising adjuvant for various medical indications, such as cancer, vascular, and neurodegenerative diseases. Additionally, resveratrol was shown to display beneficial effects on the human skin. The polyphenol is discussed to be a feasible treatment approach to accelerate wound healing and prevent the development of chronic wounds without the drawback of systemic side effects. Despite resveratrol's increasing popularity, its molecular mechanisms of action are still poorly understood. To take full advantage of resveratrol's therapeutic potential, a profound knowledge of its interactions with its targets is needed. Therefore, this review highlights the resveratrol-induced molecular pathways with particular focus on the most relevant variables in wound healing, namely inflammation, oxidative stress, autophagy, collagen proliferation and angiogenesis.

Aluminum impairs cognitive function by activating DDX3X-NLRP3-mediated pyroptosis signaling pathway

INTRODUCTION

Aluminum is a kind of chemical contaminants in food which can induce neurotoxicity. Aluminum exposure is closely related to neurodegenerative diseases (ND), in which neuroinflammation might involve. However, the molecular mechanism of aluminum-induced neuroinflammation through pyroptosis is not fully clarified yet.

MATERIAL AND METHODS

The mice model of subacute exposure to aluminum chloride (AlCl₃) was established. BV2 microglia cells was treated with AlCl₃ in vitro. Resveratrol (Rsv) was adopted as intervention agent.

RESULTS

Our results showed that aluminum induced cognitive impairment, destroying blood brain barrier (BBB), and causing nerve injury in mice. Meanwhile, aluminum could stimulate nucleotide oligomerization domain-like receptor family pyrin domain containing protein 3 (NLRP3) inflammasome assembly and activate caspase-1 (CASP1), inducing gasdermin D (GSDMD)-mediated pyroptosis signaling, releasing cytokines IL-1β and IL-18, further promoting the activation of glial cells to magnify neuroinflammatory response. Moreover, DEAD-box helicase 3 X-linked (DDX3X) and stress granule RasGAP SH3-domain-binding protein 1 (G3BP1) both participated in neuroinflammation induced by aluminum. When co-treated with Rsv, these injuries were alleviated to some extent.

CONCLUSION

Aluminum exposure could induce nerve cell pyroptosis and neuroinflammation by DDX3X-NLRP3 inflammasome signaling pathway, which could be rescued via Rsv activating sirtuin 1 (SIRT1).

Peroxisome Proliferator-Activated Receptor-Gamma (PPAR-ɣ): Molecular Effects and Its Importance as a Novel Therapeutic Target for Cerebral Ischemic Injury

Cerebral ischemic injury is a leading cause of death and long-term disability throughout the world. Peroxisome proliferator-activated receptor gamma (PPAR-ɣ) is a ligand-activated nuclear transcription factor that is a member of the PPAR family. PPAR-ɣ has been shown in several in vitro and in vivo models to prevent post-ischemic inflammation and neuronal damage by negatively controlling the expression of genes modulated by cerebral ischemic injury, indicating a neuroprotective effect during cerebral ischemic injury. A extensive literature review of PubMed, Medline, Bentham, Scopus, and EMBASE (Elsevier) databases was carried out to understand the nature of the extensive work done on the mechanistic role of Peroxisome proliferator activated receptor gamma and its modulation in Cerebral ischemic injury. PPAR-ɣ can interact with specific DNA response elements to control gene transcription and expression when triggered by its ligand. It regulates lipid metabolism, improves insulin sensitivity, modulates antitumor mechanisms, reduces oxidative stress, and inhibits inflammation. This review article provides insights on the current state of research into the neuroprotective effects of PPAR-ɣ in cerebral ischemic injury, as well as the cellular and molecular mechanisms by which these effects are modulated, such as inhibition of inflammation, reduction of oxidative stress, suppression of pro-apoptotic production, modulation of transcription factors, and restoration of injured tissue through neurogenesis and angiogenesis.

Anti-Neuroinflammatory Potential of Polyphenols by Inhibiting NF-κB to Halt Alzheimer's Disease

Alzheimer's disease (AD) is an irrevocable chronic brain disorder featured by neuronal loss, microglial accumulation, and progressive cognitive impairment. The proper pathophysiology of this life-threatening disorder is not completely understood and no exact remedies have been found yet. Over the last few decades, research on AD has mainly highlighted pathomechanisms linked to a couple of the major pathological hallmarks, including extracellular senile plaques made of amyloid-β (Aβ) peptides, and intracellular neurofibrillary tangles (NFTs) made of tau proteins. Aβ can induce apoptosis, trigger an inflammatory response, and inhibit the synaptic plasticity of the hippocampus, which ultimately contributes to reducing cognitive functions and memory impairment. Recently, a third disease hallmark, the neuroinflammatory reaction that is mediated by cerebral innate immune cells, has become a spotlight in the current research area, assured by pre-clinical, clinical, and genetic investigations. Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), a cytokine producer, is significantly associated with physiological inflammatory proceedings and thus shows a promising candidate for inflammation- based AD therapy. Recent data reveal that phytochemicals, mainly polyphenol compounds, exhibit potential neuroprotective functions and these may be considered as a vital resource for discovering several drug candidates against AD. Interestingly, phytochemicals can easily interfere with the signaling pathway of NF-κB. This review represents the anti-neuroinflammatory potential of polyphenols as inhibitors of NF-κB to combat AD pathogenesis.

Naproxen platinum(iv) hybrids inhibiting cycloxygenases and matrix metalloproteinases and causing DNA damage: synthesis and biological evaluation as antitumor agents in vitro and in vivo

Cycloxygenases (COXs) and matrix metalloproteinases (MMPs) in the tumor microenvironment (TME) are tightly related to the progression of cancers. Here, naproxen as a potent inhibitor of both COX and MMP was combined with platinum(iv) to construct hybrids as antitumor agents. Compound 2 with comparable or even superior activities to that of cisplatin, oxaliplatin, and carboplatin, great potential for reversing drug resistance, and superior tumor targeting properties was screened out as a lead compound. Moreover, compound 2 possessed potent tumor growth inhibition capability in vivo, which was comparable to that of oxaliplatin, and displayed rather lower side effects than the platinum(ii) reference drugs. The naproxen platinum(iv) complex could easily undergo reduction and liberate the platinum(ii) complex and naproxen as well as exert a multifunctional antitumor mechanism: (i) the liberated platinum(ii) fragment would cause serious DNA injury; (ii) naproxen would inhibit COX-2 and decrease tumor-associated inflammation; and (iii) the naproxen platinum(iv) complex exhibited remarkable MMP-9 inhibition in tumor tissues. These antitumor functions can help reduce the growth and metastasis of malignancy.

Geraniin Protects PC12 Cells Against Aβ25-35-Mediated Neuronal Damage: Involvement of NF-κB and MAPK Signaling Pathways

β-amyloid peptide (Aβ) has been considered a critical factor that is associated with the development of oxidative stress and neuroinflammation in the pathogenesis of Alzheimer's disease. This study was performed to evaluate the effect of geraniin on Aβ_25-35-caused oxidative damage and neuroinflammatory response, and its underlying mechanism. Geraniin protected pheochromocytoma12 (PC12) cells from Aβ_25-35-mediated cell death by reducing oxidative stress and restoring cell cycle dysregulation. Moreover, geraniin markedly attenuated Aβ-triggered DNA injury that was partially associated with decreases in caspase-3 activity. Moreover, the compound significantly downregulated the release of neuroinflammatory factors. Upregulation of nuclear factor-κB activity was suppressed by geraniin, which was due to suppression of JNK, ERK1/2, and the p38 mitogen-activated protein kinase (MAPK) pathway. This was the first study to support further understanding of geraniin as a promising agent against neurotoxicity in the reduction of oxidative stress and neuroinflammation.

Novel function of VEGF-B as an antioxidant and therapeutic implications

Oxidative stress, due to insufficiency of antioxidants or over-production of oxidants, can lead to severe cell and tissue damage. Oxidative stress occurs constantly and has been shown to be involved in innumerable diseases, such as degenerative, cardiovascular, neurological, and metabolic disorders, cancer, and aging, thus highlighting the vital need of antioxidant defense mechanisms. Vascular endothelial growth factor B (VEGF-B) was discovered a long time ago, and is abundantly expressed in most types of cells and tissues. VEGF-B remained functionally mysterious for many years and later on has been shown to be minimally angiogenic. Recently, VEGF-B is reported to be a potent antioxidant by boosting the expression of key antioxidant enzymes. Thus, one major role of VEGF-B lies in safeguarding tissues and cells from oxidative stress-induced damage. VEGF-B may therefore have promising therapeutic utilities in treating oxidative stress-related diseases. In this review, we discuss the current knowledge on the newly discovered antioxidant function of VEGF-B and the related molecular mechanisms, particularly, in relationship to some oxidative stress-related diseases, such as retinitis pigmentosa, age-related macular degeneration, diabetic retinopathy, glaucoma, amyotrophic lateral sclerosis, Alzheimer's disease, and Parkinson's disease.

Neuroprotective Mechanisms of Resveratrol in Alzheimer's Disease: Role of SIRT1

Alzheimer's disease (AD) is a progressive and neurodegenerative disorder of the cortex and hippocampus, which eventually leads to cognitive impairment. Although the etiology of AD remains unclear, the presence of β-amyloid (Aβ) peptides in these learning and memory regions is a hallmark of AD. Therefore, the inhibition of Aβ peptide aggregation has been considered the primary therapeutic strategy for AD treatment. Many studies have shown that resveratrol has antioxidant, anti-inflammatory, and neuroprotective properties and can decrease the toxicity and aggregation of Aβ peptides in the hippocampus of AD patients, promote neurogenesis, and prevent hippocampal damage. In addition, the antioxidant activity of resveratrol plays an important role in neuronal differentiation through the activation of silent information regulator-1 (SIRT1). SIRT1 plays a vital role in the growth and differentiation of neurons and prevents the apoptotic death of these neurons by deacetylating and repressing p53 activity; however, the exact mechanisms remain unclear. Resveratrol also has anti-inflammatory effects as it suppresses M1 microglia activation, which is involved in the initiation of neurodegeneration, and promotes Th2 responses by increasing anti-inflammatory cytokines and SIRT1 expression. This review will focus on the antioxidant and anti-inflammatory neuroprotective effects of resveratrol, specifically on its role in SIRT1 and the association with AD pathophysiology.

Inhibition of NF-κB Signaling Pathway by Resveratrol Improves Spinal Cord Injury

Spinal cord injury (SCI) can have a significant impact on an individual’s life. Herein, we discuss how resveratrol improves SCI by inhibiting nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling pathway. Evidences show resveratrol suppresses NF-κB signaling pathway to exert its beneficial effects on various diseases. NF-κB signaling pathway plays a significant role in the pathophysiological mechanisms of SCI including increase in inflammation, augmentation of damage caused by free radicals and lipid peroxidation as well as facilitation of apoptosis and axonal demyelination. We also discuss mechanisms between resveratrol and NF-κB signaling pathway in the wake of SCI, which can be potential targets for resveratrol to treat SCI.

Asiaticoside Attenuates Cell Growth Inhibition and Apoptosis Induced by Aβ1-42 via Inhibiting the TLR4/NF-κB Signaling Pathway in Human Brain Microvascular Endothelial Cells

Alzheimer's disease (AD) is a very common progressive neurodegenerative disorder with the highest incidence in the world. Dysfunction of the blood-brain barrier (BBB) may be responsible for the pathogenesis and pathology of AD for abnormally transporting amyloid-β (Aβ, the main component of the senile plaques) from the sera into the central nervous system. Aβ peptides induce apoptosis in human brain microvascular endothelial cells (hBMECs), the main component of BBB. Apoptosis in neuronal cells plays a critical role in the pathogenesis of AD. Asiaticoside, a natural glycoside extracted from Centella asiatica (L.) Urban, has an anti-apoptotic effect on hBMECs but the molecule mechanism remains unclear. Therefore, we investigate the protective effect of asiaticoside on Aβ_1-42-induced cytotoxicity and apoptosis as well as associated mechanism in hBMECs with commonly used in vitro methods for clinical development of asiaticoside as a novel anti-AD agent. In the present study, we investigated the effects of asiaticoside on cytotoxicity by Cell Counting Kit-8 assay, mitochondrial membrane potential by JC-1 fluorescence analysis, anti-apoptosis by Hoechst 33258 staining and Annexin V-FITC (fluorescein isothiocyanate) and propidium iodide (PI) analyses, the expressions of TNF-α and IL-6 by enzyme-linked immunosorbent assay (ELISA) and TLR4, MyD88, TRAF6, p-NF-κB p65, and total NF-κB p65 by Western blotting, and nuclear translocation of NF-κB p65 by immunofluorescence analysis in hBMECs. The results showed that pretreatment of asiaticoside (25, 50, and 100 μM) for 12 h significantly attenuated cell growth inhibition and apoptosis, and restored declined mitochondrial membrane potential induced by Aβ_1-42 (50 μM) in hBMECs. Asiaticoside also significantly downregulated the elevated expressions of TNF-α, IL-6, TLR4, MyD88, TRAF6, and p-NF-κB p65, as well as inhibited NF-κB p65 translocation from cytoplasm to nucleus induced by Aβ_1-42 in hBMECs in a concentration-dependent manner. The possible underlying molecular mechanism of asiaticoside may be through inhibiting the TLR4/NF-κB signaling pathway. Therefore, asiaticoside may be developed as a novel agent for the prevention and/or treatment of AD clinically.

Potential implications of Apolipoprotein E in early brain injury after experimental subarachnoid hemorrhage: Involvement in the modulation of blood-brain barrier integrity

Apolipoprotein E (Apoe) genetic polymorphisms have been implicated in the long term outcome of subarachnoid haemorrhage (SAH), but little is known about the effect of Apoe on the early brain injury (EBI) after SAH. This study investigated the potential role of APOE in EBI post-SAH. Multiple techniques were used to determine the early BBB disruption in EBI post-SAH in a murine model using wild-type (WT) and Apoe^−/− (KO) mice. Progressive BBB disruption (Evans blue extravasation and T2 hyperintensity in magnetic resonance imaging) was observed before the peak of endogenous APOE expression elevation at 48h after SAH. Moreover, Apoe^−/− mice exhibited more severe BBB disruption charcteristics after SAH than WT mice, including higher levels of Evans blue and IgG extravasation, T2 hyperintensity in magnetic resonance imaging, tight junction proteins degradation and endothelial cells death. Mechanistically, we found that APOE restores the BBB integrity in the acute stage after SAH via the cyclophilin A (CypA)-NF-κB-proinflammatory cytokines-MMP-9 signalling pathway. Consequently, although early BBB disruption causes neurological dysfunctions after SAH, we capture a different aspect of the effects of APOE on EBI after SAH that previous studies had overlooked and open up the idea of BBB disruption as a target of APOE-based therapy for EBI amelioration research in the future.

Thrombopoietin could protect cerebral tissue against ischemia-reperfusion injury by suppressing NF-κB and MMP-9 expression in rats

Objective: To determine the neuroprotective effects and underpinning mechanisms of thrombopoietin (TPO), Matrix Metalloproteinase-9(MMP-9) and Nuclear Factor-κB (NF-κB) after focal cerebral ischemia-reperfusion in rats. Methods: Male rats underwent 2 hours of right middle cerebral artery occlusion (MCAO) followed by 22 hours of reperfusion. PBS or TPO (0.1ug/kg) was administered from caudal vein before reperfusion. Neurologic deficits, brain edema, Evans blue (EB) extravasation, NF-κB and MMP-9 expression were subsequently examined. Results: Ischemia-reperfusion injury produced a large area of edema. TPO significantly reduced edema and alleviated neurologic deficits after ischemia-reperfusion. Ischemia-induced increases of NF-κB, MMP-9 and Evans blue extravasation were reduced by TPO intervention. Conclusion: TPO improved neurological function and ameliorated brain edema after stroke, partly by reducing the ischemia-induced increase of NF-κB and MMP-9.

Roles of Peroxisome Proliferator-Activated Receptor Gamma on Brain and Peripheral Inflammation

Peroxisome proliferator-activated receptor gamma (PPARγ) has been implicated in the pathology of numerous diseases involving diabetes, stroke, cancer, or obesity. It is expressed in diverse cell types, including vessels, immune and glial cells, and neurons. PPARγ plays crucial roles in the regulation of cellular differentiation, lipid metabolism, or glucose homeostasis. PPARγ ligands also exert effects on attenuating degenerative processes in the brain, as well as in peripheral systems, and it has been associated with the control of anti-inflammatory mechanisms, oxidative stress, neuronal death, neurogenesis, differentiation, and angiogenesis. This review will highlight key advances in the understanding of the PPARγ-related mechanisms responsible for neuroprotection after brain injuries, both ischemia and traumatic brain injury, and it will also cover the natural and synthetic agonist for PPARγ, angiotensin receptor blockers, and PPARγ antagonists, used in experimental and clinical research. A better understanding of the pleiotropic mechanisms and applications of these drugs to improve the recovery and to repair the acute and chronic induced neuroinflammation after brain injuries will pave the way for more effective therapeutic strategies after brain deficits.

A study of Sirt1 regulation and the effect of resveratrol on synoviocyte invasion and associated joint destruction in rheumatoid arthritis

The aim of the current study was to investigate the role and mechanism of sirtuin 1 (Sirt1) in the regulation of synovial cell invasion and joint destruction in rheumatoid arthritis (RA). The Sirt1 protein and mRNA levels in fibroblast‑like synoviocytes (FLS) isolated from RA synovial tissues were compared with normal tissues by western blot and reverse transcription‑polymerase chain reaction. RA FLS were then treated with the Sirt1 agonist resveratrol (1, 3 and 10 µg/ml) for 48 h, and their invasiveness and expression of matrix metalloproteinase (MMP) 1 and MMP13 protein and mRNA were measured. Furthermore, a collagen‑induced arthritis (CIA) rat model was established and the rats were divided into a model group, and low‑ and high‑dose resveratrol (2.5 and 10 mg/kg/day) groups to receive an intraperitoneal injection of resveratrol for 42 consecutive days. The joint morphology, arthritis index (AI), and MMP1 and MMP13 expression in synovial tissues was monitored. The Sirt1 protein and mRNA levels in RA FLS were significantly lower compared with normal FLS (P<0.01). The resveratrol treatment significantly inhibited the invasive ability of RA FLS (P<0.01) and reduced MMP1 and MMP13 expression (P<0.01). The AI in low‑ and high‑dose groups was significantly lower compared with the model group from day 28 (P<0.01). Resveratrol also reduced the swelling and damage and decreased MMP1 and MMP13 expression levels in CIA rats (P<0.01). The resveratrol‑induced upregulation of Sirt1 in RA FLS may significantly inhibit the invasion of these cells and reduce the degree of joint damage, which may be mediated through the inhibition of MMP1 and MMP13 expression. The present results suggested a regulatory role for Sirt1 in RA pathogenesis, and demonstrated the beneficial effects of resveratrol, which may have potential as an alternative therapeutic strategy for the treatment of patients with RA.

Targeting extracellular matrix remodeling in disease: Could resveratrol be a potential candidate?

Disturbances of extracellular matrix homeostasis are associated with a number of pathological conditions. The ability of extracellular matrix to provide contextual information and hence control the individual or collective cellular behavior is increasingly being recognized. Hence, newer therapeutic approaches targeting extracellular matrix remodeling are widely investigated. We reviewed the current literature showing the effects of resveratrol on various aspects of extracellular matrix remodeling. This review presents a summary of the effects of resveratrol on extracellular matrix deposition and breakdown. Mechanisms of action of resveratrol in extracellular matrix deposition involving growth factors and their signaling pathways are discussed. Involvement of phosphoinositol-3-kinase/Akt and mitogen-activated protein kinase pathways and role of transcription factors and sirtuins on the effects of resveratrol on extracellular matrix homeostasis are summarized. It is evident from the literature presented in this review that resveratrol has significant effects on both the synthesis and breakdown of extracellular matrix. The major molecular targets of the action of resveratrol are growth factors and their signaling pathways, phosphoinositol-3-kinase/Akt and mitogen-activated protein kinase pathways, transcription factors, and SIRT-1. The effects of resveratrol on extracellular matrix and the molecular targets appear to be related to experimental models, experimental environment as well as the doses.

Resveratrol and Ophthalmic Diseases

Resveratrol, a naturally occurring plant polyphenol found in grapes, is the principal biologically active component in red wine. Clinical studies have shown that resveratrol due to its potent anti-oxidant and anti-inflammatory properties are cardio-protective, chemotherapeutic, neuroprotective, and display anti-aging effects. Oxidative stress and inflammation play a critical role in the initiation and progression of age-related ocular diseases (glaucoma, cataract, diabetic retinopathy and macular degeneration) that lead to progressive loss of vision and blindness. In vitro and in vivo (animal model) experimental studies performed so far have provided evidence for the biological effects of resveratrol on numerous pathways including oxidative stress, inflammation, mitochondrial dysfunction, apoptosis, pro-survival or angiogenesis that are implicated in the pathogenesis of these age-related ocular disorders. In this review, we provide a brief overview of current scientific literature on resveratrol, its plausible mechanism(s) of action, its potential use and current limitations as a nutritional therapeutic intervention in the eye and its related disorders.

Comparison of antidiabetic potential of (+) and (−)-hopeaphenol, a pair of enantiomers isolated from Ampelocissus indica (L.) and Vateria indica Linn., with respect to inhibition of digestive enzymes and induction of glucose uptake in L6 myotubes

The remarkable α-glucosidase inhibition exhibited by the acetone extract of the rhizome ofAmpelocissus indica(L.) and stem bark ofVateria indicaLinn. (IC₅₀23.2 and 1.47 μg mL⁻¹) encouraged us to isolate the phytochemicals from these plants.

Aterofisiol(®) in carotid plaque evolution

Background

In patients with carotid stenosis, the risk of plaque rupture is related to the composition of the atherosclerotic plaque rather than to its magnitude. In this regard, we evaluated the effects of a supplement, Aterofisiol,^® containing omega-3 (EPA [eicosapen acid] DHA [docosahexaenoic acid]), vitamin K₂, vitamin B₆, vitamin B₁₂, oligomeric proanthocyanidins (OPC) and resveratrol on the composition of atherosclerotic plaque and on neurological symptoms in patients with carotid stenosis undergoing carotid endarterectomy.

Methods

The study was randomized, prospective, and double-blinded. Eligible patients were of both sexes, with carotid stenosis >70% who underwent endarterectomy. Enrolled patients were randomly allocated to receive either one tablet of acetylsalicylic acid 100 mg (Cardioaspirin^®) + one tablet of Aterofisiol every 24 hours or one tablet of Cardioaspirin + one tablet of placebo every 24 hours. Each treatment was started 30 days before the surgery and was stopped 5 days before the surgery. The plaques were removed “en bloc” using standard surgical technique.

Results

During the study period, 214 patients (135 men and 79 women) were enrolled for intent-to-treat and randomized in two groups: Group A: 107 patients (68 men and 39 women) were treated with Cardioaspirin + Aterofisiol. Group B: 107 patients (67 men and 40 women) were treated with Cardioaspirin + placebo. At the end of the study, 202 patients participated fully (103 patients in Group A and 99 patients in Group B), making up the protocol evaluation population (94.4%). The mean lipid content of removed plaques was significantly lower (P<0.05) in Group A. We recorded a significantly lower incidence of neurological symptoms in Group A in comparison with Group B (P<0.05).

Conclusion

In the study, Aterofisiol showed to be effective in reducing the amounts of cholesterol and lipids in the plaques and in reducing adverse neurological events in the study group with respect to controls.

A Role for the Cavin-3/Matrix Metalloproteinase-9 Signaling Axis in the Regulation of PMA-Activated Human HT1080 Fibrosarcoma Cell Neoplastic Phenotype

Caveolae are specialized cell membrane invaginations known to regulate several cancer cell functions and oncogenic signaling pathways. Among other caveolar proteins, they are characterized by the presence of proteins of the cavin family. In this study, we assessed the impact of cavin-1, cavin-2, and cavin-3 on cell migration in a human HT-1080 fibrosarcoma model. We found that all cavin-1, -2 and -3 transcripts were expressed and that treatment with phorbol 12-myristate 13-acetate (PMA), which is known to prime cell migration and proliferation, specifically upregulated cavin-3 gene and protein expression. PMA also triggered matrix metalloproteinase (MMP)-9 secretion, but reduced the global cell migration index. Overexpression of recombinant forms of the three cavins demonstrated that only cavin-3 was able to reduce basal cell migration, and this anti-migratory effect was potentiated by PMA. Interestingly, cavin-3 overexpression inhibited PMA-induced MMP-9, while cavin-3 gene silencing led to an increase in MMP-9 gene expression and secretion. Furthermore, recombinant cavin-3 significantly prevented PMA-mediated dephosphorylation of AKT, a crucial regulator in MMP-9 transcription. In conclusion, our results demonstrate that cellular cavin-3 expression may repress MMP-9 transcriptional regulation in part through AKT. We suggest that the balance in cavin-3-to-MMP-9 expression regulates the extent of extracellular matrix degradation, confirming the tumor-suppressive role of cavin-3 in controlling the invasive potential of human fibrosarcoma cells.

Resveratrol and cardiovascular health--promising therapeutic or hopeless illusion?

Resveratrol (3,5,4'-trihydroxy-trans-stilbene) is a natural polyphenolic compound that exists in Polygonum cuspidatum, grapes, peanuts and berries, as well as their manufactured products, especially red wine. Resveratrol is a pharmacologically active compound that interacts with multiple targets in a variety of cardiovascular disease models to exert protective effects or induce a reduction in cardiovascular risks parameters. This review attempts to primarily serve to summarize the current research findings regarding the putative cardioprotective effects of resveratrol and the molecular pathways underlying these effects. One intent is to hopefully provide a relatively comprehensive resource for clues that may prompt ideas for additional mechanistic studies which might further elucidate and strengthen the role of the stilbene family of compounds in cardiovascular disease and cardioprotection. Model systems that incorporate a significant functional association with tissues outside of the cardiovascular system proper, such as adipose (cell culture, obesity models) and pancreatic (diabetes) tissues, were reviewed, and the molecular pathways and/or targets related to these models and influenced by resveratrol are discussed. Because the body of work encompassing the stilbenes and other phytochemicals in the context of longevity and the ability to presumably mitigate a plethora of afflictions is replete with conflicting information and controversy, especially so with respect to the human response, we tried to remain as neutral as possible in compiling and presenting the more current data with minimal commentary, permitting the reader free reign to extract the knowledge most helpful to their own investigations.

Resveratrol and clinical trials: the crossroad from in vitro studies to human evidence

Resveratrol (3,5,4’-trihydroxy-trans-stilbene) is a non-flavonoid polyphenol that may be present in a limited number of food-stuffs such as grapes and red wine. Resveratrol has been reported to exert a plethora of health benefits through many different mechanisms of action. This versatility and presence in the human diet have drawn the worldwide attention of many research groups over the past twenty years, which has resulted in a huge output of in vitro and animal (preclinical) studies. In line with this expectation, many resveratrol-based nutraceuticals are consumed all over the world with questionable clinical/scientific support. In fact, the confirmation of these benefits in humans through randomized clinical trials is still very limited. The vast majority of preclinical studies have been performed using assay conditions with a questionable extrapolation to humans, i.e. too high concentrations with potential safety concerns (adverse effects and drug interactions), short-term exposures, in vitro tests carried out with non-physiological metabolites and/or concentrations, etc. Unfortunately, all these hypothesis-generating studies have contributed to increased the number of ‘potential’ benefits and mechanisms of resveratrol but confirmation in humans is very limited. Therefore, there are many issues that should be addressed to avoid an apparent endless loop in resveratrol research. The so-called ‘Resveratrol Paradox’, i.e., low bioavailability but high bioactivity, is a conundrum not yet solved in which the final responsible actor (if any) for the exerted effects has not yet been unequivocally identified. It is becoming evident that resveratrol exerts cardioprotective benefits through the improvement of inflammatory markers, atherogenic profile, glucose metabolism and endothelial function. However, safety concerns remain unsolved regarding chronic consumption of high RES doses, specially in medicated people. This review will focus on the currently available evidence regarding resveratrol’s effects on humans obtained from randomized clinical trials. In addition, we will provide a critical outlook for further research on this molecule that is evolving from a minor dietary compound to a possible multi-target therapeutic drug.

SIRT1 suppresses cellular accumulation of β-TrCP E3 ligase via protein degradation

β-Transducin repeat-containing protein (β-TrCP), an E3 ligase, promotes the degradation of substrate proteins in response to various stimuli. Even though several β-TrCP substrates have been identified to date, limited information of its upstream regulators is available. Here, we showed that SIRT1 suppresses β-TrCP protein synthesis via post-translational degradation. SIRT1 depletion led to a significant increase in the β-TrCP accumulation without affecting the mRNA level. Consistently, β-TrCP protein accumulation induced by resveratrol was further enhanced upon SIRT1 depletion. Rescue of SIRT1 reversed the effect of resveratrol, leading to reduced β-TrCP protein levels. Proteasomal inhibition led to recovery of β-TrCP in cells with SIRT1 overexpression. Notably, the recovered β-TrCP colocalized mostly with SIRT1. Thus, SIRT1 acts as a negative regulator of β-TrCP synthesis via promoting protein degradation.

Seven sirtuins for seven deadly diseases of aging

Sirtuins are a class of NAD(+)-dependent deacetylases having beneficial health effects. This extensive review describes the numerous intracellular actions of the seven mammalian sirtuins, their protein targets, intracellular localization, the pathways they modulate, and their role in common diseases of aging. Selective pharmacological targeting of sirtuins is of current interest in helping to alleviate global disease burden. Since all sirtuins are activated by NAD(+), strategies that boost NAD(+) in cells are of interest. While most is known about SIRT1, the functions of the six other sirtuins are now emerging. Best known is the involvement of sirtuins in helping cells adapt energy output to match energy requirements. SIRT1 and some of the other sirtuins enhance fat metabolism and modulate mitochondrial respiration to optimize energy harvesting. The AMP kinase/SIRT1-PGC-1α-PPAR axis and mitochondrial sirtuins appear pivotal to maintaining mitochondrial function. Downregulation with aging explains much of the pathophysiology that accumulates with aging. Posttranslational modifications of sirtuins and their substrates affect specificity. Although SIRT1 activation seems not to affect life span, activation of some of the other sirtuins might. Since sirtuins are crucial to pathways that counter the decline in health that accompanies aging, pharmacological agents that boost sirtuin activity have clinical potential in treatment of diabetes, cardiovascular disease, dementia, osteoporosis, arthritis, and other conditions. In cancer, however, SIRT1 inhibitors could have therapeutic value. Nutraceuticals such as resveratrol have a multiplicity of actions besides sirtuin activation. Their net health benefit and relative safety may have originated from the ability of animals to survive environmental changes by utilizing these stress resistance chemicals in the diet during evolution. Each sirtuin forms a key hub to the intracellular pathways affected.